I can search for tasks I subscribe to. I can search for tasks I am assigned.

But I want to see the stuff that I'm subscribed to, but not assigned - a sort of "keep an eye on this stuff" list.

I can get sort of close by grouping on assignee, but this is less helpful if I am near the top of the alphabetical order, because groups don't appear to be sortable.

Is there some other way to do a "NOT" query like this?