diff --git a/resources/celerity/map.php b/resources/celerity/map.php
--- a/resources/celerity/map.php
+++ b/resources/celerity/map.php
@@ -9,11 +9,11 @@
   'names' => array(
     'conpherence.pkg.css' => 'ff161f2d',
     'conpherence.pkg.js' => 'b5b51108',
-    'core.pkg.css' => 'a5a2d647',
-    'core.pkg.js' => '0f87a6eb',
+    'core.pkg.css' => '4937a7d7',
+    'core.pkg.js' => 'a0c8fb20',
     'darkconsole.pkg.js' => '1f9a31bc',
-    'differential.pkg.css' => '697405d4',
-    'differential.pkg.js' => '07c56ffc',
+    'differential.pkg.css' => '52b014e7',
+    'differential.pkg.js' => '1efe85bf',
     'diffusion.pkg.css' => 'b93d9b8c',
     'diffusion.pkg.js' => '84c8f8fd',
     'favicon.ico' => '30672e08',
@@ -64,7 +64,7 @@
     'rsrc/css/application/dashboard/dashboard.css' => 'fe5b1869',
     'rsrc/css/application/diff/inline-comment-summary.css' => '51efda3a',
     'rsrc/css/application/differential/add-comment.css' => 'c47f8c40',
-    'rsrc/css/application/differential/changeset-view.css' => '15be1064',
+    'rsrc/css/application/differential/changeset-view.css' => 'e7bd2a79',
     'rsrc/css/application/differential/core.css' => '5b7b8ff4',
     'rsrc/css/application/differential/phui-inline-comment.css' => 'ffd1a542',
     'rsrc/css/application/differential/revision-comment.css' => '14b8565a',
@@ -116,7 +116,7 @@
     'rsrc/css/core/core.css' => '9f4cb463',
     'rsrc/css/core/remarkup.css' => 'd1a5e11e',
     'rsrc/css/core/syntax.css' => 'cae95e89',
-    'rsrc/css/core/z-index.css' => '0233d039',
+    'rsrc/css/core/z-index.css' => '9d8f7c4b',
     'rsrc/css/diviner/diviner-shared.css' => '896f1d43',
     'rsrc/css/font/font-awesome.css' => 'e838e088',
     'rsrc/css/font/font-lato.css' => 'c7ccd872',
@@ -390,8 +390,8 @@
     'rsrc/js/application/dashboard/behavior-dashboard-move-panels.js' => '408bf173',
     'rsrc/js/application/dashboard/behavior-dashboard-query-panel-select.js' => '453c5375',
     'rsrc/js/application/dashboard/behavior-dashboard-tab-panel.js' => 'd4eecc63',
-    'rsrc/js/application/diff/DiffChangeset.js' => '731125f3',
-    'rsrc/js/application/diff/DiffChangesetList.js' => '59d1ceb1',
+    'rsrc/js/application/diff/DiffChangeset.js' => '3268dd83',
+    'rsrc/js/application/diff/DiffChangesetList.js' => '0a4f7809',
     'rsrc/js/application/diff/DiffInline.js' => '3337c065',
     'rsrc/js/application/diff/behavior-preview-link.js' => '051c7832',
     'rsrc/js/application/differential/behavior-comment-preview.js' => 'b064af76',
@@ -503,7 +503,7 @@
     'rsrc/js/core/behavior-more.js' => 'a80d0378',
     'rsrc/js/core/behavior-object-selector.js' => 'e0ec7f2f',
     'rsrc/js/core/behavior-oncopy.js' => '2926fff2',
-    'rsrc/js/core/behavior-phabricator-nav.js' => '08163386',
+    'rsrc/js/core/behavior-phabricator-nav.js' => '947753e0',
     'rsrc/js/core/behavior-phabricator-remarkup-assist.js' => 'acd29eee',
     'rsrc/js/core/behavior-read-only-warning.js' => 'ba158207',
     'rsrc/js/core/behavior-refresh-csrf.js' => 'ab2f381b',
@@ -565,7 +565,7 @@
     'conpherence-thread-manager' => '4d863052',
     'conpherence-transaction-css' => '85129c68',
     'd3' => 'a11a5ff2',
-    'differential-changeset-view-css' => '15be1064',
+    'differential-changeset-view-css' => 'e7bd2a79',
     'differential-core-view-css' => '5b7b8ff4',
     'differential-revision-add-comment-css' => 'c47f8c40',
     'differential-revision-comment-css' => '14b8565a',
@@ -658,7 +658,7 @@
     'javelin-behavior-phabricator-keyboard-pager' => 'a8da01f0',
     'javelin-behavior-phabricator-keyboard-shortcuts' => '01fca1f0',
     'javelin-behavior-phabricator-line-linker' => '1499a8cb',
-    'javelin-behavior-phabricator-nav' => '08163386',
+    'javelin-behavior-phabricator-nav' => '947753e0',
     'javelin-behavior-phabricator-notification-example' => '8ce821c5',
     'javelin-behavior-phabricator-object-selector' => 'e0ec7f2f',
     'javelin-behavior-phabricator-oncopy' => '2926fff2',
@@ -775,8 +775,8 @@
     'phabricator-darklog' => 'c8e1ffe3',
     'phabricator-darkmessage' => 'c48cccdd',
     'phabricator-dashboard-css' => 'fe5b1869',
-    'phabricator-diff-changeset' => '731125f3',
-    'phabricator-diff-changeset-list' => '59d1ceb1',
+    'phabricator-diff-changeset' => '3268dd83',
+    'phabricator-diff-changeset-list' => '0a4f7809',
     'phabricator-diff-inline' => '3337c065',
     'phabricator-drag-and-drop-file-upload' => '58dea2fa',
     'phabricator-draggable-list' => 'bea6e7f4',
@@ -816,7 +816,7 @@
     'phabricator-uiexample-reactor-select' => 'a155550f',
     'phabricator-uiexample-reactor-sendclass' => '1def2711',
     'phabricator-uiexample-reactor-sendproperties' => 'b1f0ccee',
-    'phabricator-zindex-css' => '0233d039',
+    'phabricator-zindex-css' => '9d8f7c4b',
     'phame-css' => 'b3a0b3a3',
     'pholio-css' => 'ca89d380',
     'pholio-edit-css' => '07676f51',
@@ -946,16 +946,6 @@
       'javelin-stratcom',
       'javelin-workflow',
     ),
-    '08163386' => array(
-      'javelin-behavior',
-      'javelin-behavior-device',
-      'javelin-stratcom',
-      'javelin-dom',
-      'javelin-magical-init',
-      'javelin-vector',
-      'javelin-request',
-      'javelin-util',
-    ),
     '0825c27a' => array(
       'javelin-behavior',
       'javelin-dom',
@@ -983,6 +973,9 @@
       'javelin-dom',
       'javelin-router',
     ),
+    '0a4f7809' => array(
+      'javelin-install',
+    ),
     '0f764c35' => array(
       'javelin-install',
       'javelin-util',
@@ -999,9 +992,6 @@
       'javelin-dom',
       'javelin-history',
     ),
-    '15be1064' => array(
-      'phui-inline-comment-view-css',
-    ),
     '17bb8539' => array(
       'javelin-behavior',
       'javelin-stratcom',
@@ -1122,6 +1112,17 @@
       'javelin-dom',
       'javelin-vector',
     ),
+    '3268dd83' => array(
+      'javelin-dom',
+      'javelin-util',
+      'javelin-stratcom',
+      'javelin-install',
+      'javelin-workflow',
+      'javelin-router',
+      'javelin-behavior-device',
+      'javelin-vector',
+      'phabricator-diff-inline',
+    ),
     '327a00d1' => array(
       'javelin-behavior',
       'javelin-stratcom',
@@ -1349,9 +1350,6 @@
       'javelin-vector',
       'javelin-dom',
     ),
-    '59d1ceb1' => array(
-      'javelin-install',
-    ),
     '5c54cbf3' => array(
       'javelin-behavior',
       'javelin-stratcom',
@@ -1450,17 +1448,6 @@
       'javelin-workflow',
       'phabricator-draggable-list',
     ),
-    '731125f3' => array(
-      'javelin-dom',
-      'javelin-util',
-      'javelin-stratcom',
-      'javelin-install',
-      'javelin-workflow',
-      'javelin-router',
-      'javelin-behavior-device',
-      'javelin-vector',
-      'phabricator-diff-inline',
-    ),
     '7319e029' => array(
       'javelin-behavior',
       'javelin-dom',
@@ -1619,6 +1606,16 @@
       'javelin-workflow',
       'javelin-dom',
     ),
+    '947753e0' => array(
+      'javelin-behavior',
+      'javelin-behavior-device',
+      'javelin-stratcom',
+      'javelin-dom',
+      'javelin-magical-init',
+      'javelin-vector',
+      'javelin-request',
+      'javelin-util',
+    ),
     '949c0fe5' => array(
       'javelin-install',
     ),
@@ -2127,6 +2124,9 @@
       'javelin-workflow',
       'javelin-magical-init',
     ),
+    'e7bd2a79' => array(
+      'phui-inline-comment-view-css',
+    ),
     'e9581f08' => array(
       'javelin-behavior',
       'javelin-stratcom',
diff --git a/src/applications/differential/view/DifferentialChangesetDetailView.php b/src/applications/differential/view/DifferentialChangesetDetailView.php
--- a/src/applications/differential/view/DifferentialChangesetDetailView.php
+++ b/src/applications/differential/view/DifferentialChangesetDetailView.php
@@ -183,6 +183,7 @@
           'autoload' => $this->getAutoload(),
           'loaded' => $this->getLoaded(),
           'undoTemplates' => hsprintf('%s', $renderer->renderUndoTemplates()),
+          'path' => $display_filename,
         ),
         'class' => $class,
         'id'    => $id,
diff --git a/webroot/rsrc/css/application/differential/changeset-view.css b/webroot/rsrc/css/application/differential/changeset-view.css
--- a/webroot/rsrc/css/application/differential/changeset-view.css
+++ b/webroot/rsrc/css/application/differential/changeset-view.css
@@ -386,3 +386,21 @@
 .differential-review-stage {
   position: relative;
 }
+
+.diff-banner {
+  position: fixed;
+  top: 0;
+  left: 0;
+  right: 0;
+  background: rgba(255, 255, 255, 0.95);
+  box-shadow: 0px 1px 3px rgba(0, 0, 0, 0.1);
+  border-bottom: 1px solid {$lightgreyborder};
+  padding: 12px 18px;
+  vertical-align: middle;
+  font-weight: bold;
+  font-size: {$biggerfontsize};
+}
+
+.diff-banner .phui-icon-view {
+  margin-right: 4px;
+}
diff --git a/webroot/rsrc/css/core/z-index.css b/webroot/rsrc/css/core/z-index.css
--- a/webroot/rsrc/css/core/z-index.css
+++ b/webroot/rsrc/css/core/z-index.css
@@ -93,6 +93,10 @@
   z-index: 6;
 }
 
+.diff-banner {
+  z-index: 6;
+}
+
 .conpherence-durable-column {
   z-index: 7;
 }
diff --git a/webroot/rsrc/js/application/diff/DiffChangeset.js b/webroot/rsrc/js/application/diff/DiffChangeset.js
--- a/webroot/rsrc/js/application/diff/DiffChangeset.js
+++ b/webroot/rsrc/js/application/diff/DiffChangeset.js
@@ -19,6 +19,7 @@
     this._node = node;
 
     var data = this._getNodeData();
+
     this._renderURI = data.renderURI;
     this._ref = data.ref;
     this._whitespace = data.whitespace;
@@ -30,6 +31,8 @@
     this._leftID = data.left;
     this._rightID = data.right;
 
+    this._path = data.path;
+
     this._inlines = [];
   },
 
@@ -58,6 +61,7 @@
     _visible: true,
 
     _undoNode: null,
+    _path: null,
 
     getLeftChangesetID: function() {
       return this._leftID;
@@ -227,6 +231,9 @@
       JX.Router.getInstance().queue(routable);
     },
 
+    getPath: function() {
+      return this._path;
+    },
 
     /**
      * Receive a response to a context request.
@@ -428,6 +435,13 @@
       return JX.Stratcom.getData(this._node);
     },
 
+    getVectors: function() {
+      return {
+        pos: JX.$V(this._node),
+        dim: JX.Vector.getDim(this._node)
+      };
+    },
+
     _onresponse: function(sequence, response) {
       if (sequence != this._sequence) {
         // If this isn't the most recent request, ignore it. This normally
diff --git a/webroot/rsrc/js/application/diff/DiffChangesetList.js b/webroot/rsrc/js/application/diff/DiffChangesetList.js
--- a/webroot/rsrc/js/application/diff/DiffChangesetList.js
+++ b/webroot/rsrc/js/application/diff/DiffChangesetList.js
@@ -51,6 +51,9 @@
     var onresize = JX.bind(this, this._ifawake, this._onresize);
     JX.Stratcom.listen('resize', null, onresize);
 
+    var onscroll = JX.bind(this, this._ifawake, this._onscroll);
+    JX.Stratcom.listen('scroll', null, onscroll);
+
     var onselect = JX.bind(this, this._ifawake, this._onselect);
     JX.Stratcom.listen(
       'mousedown',
@@ -113,6 +116,8 @@
     _rangeOrigin: null,
     _rangeTarget: null,
 
+    _bannerNode: null,
+
     sleep: function() {
       this._asleep = true;
 
@@ -807,6 +812,12 @@
       this._redrawFocus();
       this._redrawSelection();
       this._redrawHover();
+
+      this._redrawBanner();
+    },
+
+    _onscroll: function() {
+      this._redrawBanner();
     },
 
     _onselect: function(e) {
@@ -1265,6 +1276,77 @@
       this._rangeTarget = null;
 
       this.resetHover();
+    },
+
+    _redrawBanner: function() {
+      var node = this._getBannerNode();
+      var changeset = this._getVisibleChangeset();
+
+      // Don't do anything if nothing has changed. This seems to avoid some
+      // flickering issues in Safari, at least.
+      if (this._bannerChangeset === changeset) {
+        return;
+      }
+      this._bannerChangeset = changeset;
+
+      if (!changeset) {
+        JX.DOM.remove(node);
+        return;
+      }
+
+      var icon = new JX.PHUIXIconView()
+        .setIcon('fa-file')
+        .getNode();
+      JX.DOM.setContent(node, [icon, ' ', changeset.getPath()]);
+
+      document.body.appendChild(node);
+    },
+
+    _getBannerNode: function() {
+      if (!this._bannerNode) {
+        var attributes = {
+          className: 'diff-banner',
+          id: 'diff-banner'
+        };
+
+        this._bannerNode = JX.$N('div', attributes);
+      }
+
+      return this._bannerNode;
+    },
+
+    _getVisibleChangeset: function() {
+      if (this.isAsleep()) {
+        return null;
+      }
+
+      if (JX.Device.getDevice() != 'desktop') {
+        return null;
+      }
+
+      // Never show the banner if we're very near the top of the page.
+      var margin = 480;
+      var s = JX.Vector.getScroll();
+      if (s.y < margin) {
+        return null;
+      }
+
+      var v = JX.Vector.getViewport();
+      for (var ii = 0; ii < this._changesets.length; ii++) {
+        var changeset = this._changesets[ii];
+        var c = changeset.getVectors();
+
+        // If the changeset starts above the upper half of the screen...
+        if (c.pos.y < (s.y + (v.y / 2))) {
+          // ...and ends below the lower half of the screen, this is the
+          // current visible changeset.
+          if ((c.pos.y + c.dim.y) > (s.y + (v.y / 2))) {
+            return changeset;
+          }
+        }
+      }
+
+      return null;
     }
   }
 
diff --git a/webroot/rsrc/js/core/behavior-phabricator-nav.js b/webroot/rsrc/js/core/behavior-phabricator-nav.js
--- a/webroot/rsrc/js/core/behavior-phabricator-nav.js
+++ b/webroot/rsrc/js/core/behavior-phabricator-nav.js
@@ -130,8 +130,19 @@
       return;
     }
 
+    // When the buoyant header is visible, move the menu down below it. This
+    // is a bit of a hack.
+    var banner_height = 0;
+    try {
+      var banner = JX.$('diff-banner');
+      banner_height = JX.Vector.getDim(banner).y;
+    } catch (error) {
+      // Ignore if there's no banner on the page.
+    }
+
     local.style.top = Math.max(
       0,
+      banner_height,
       JX.$V(content).y - Math.max(0, JX.Vector.getScroll().y)) + 'px';
   }