I have a TV tab which I populate with "Add to RTM!". I'd like to create a smart list for all "real" tasks - which wouldn't include watching TV.

If the "Search" dropdown that displays my lists were multi-select, I could select all but TV and have a list of the things I actually need to do.

A "Not tagged with" text box or minus "-" option in the "Tagged with" box could accomplish the same thing....