Today I added a feature which lets people pin threads to the top of the catalog in a much quicker manner than setting up filters.
Alt-clicking a thumbnail will now put the thread on top and track the number of new replies since the last update*.
Alt-clicking the thumbnail again will unpin the thread. Firefox master race can also clear pinned and hidden threads using the right click context menu.
edit: The key combination can be changed to Ctrl-click from the Theme menu.
Pinned threads are automatically cleared at the end of the session.
Not sure if it's really a good idea to override the default Ctrl-click behaviour, though.
*not exactly true, but whatever