Gmail search bookmarks
I've found a few Gmail searches to be very valuble in my email management. The main search I use is [(label:inbox label:unread) OR label:star] - that is, unread items from my inbox plus all my starred items. This search turns gmail's read/archive pattern on its head - once I've read a message, it disappears from view unless I take explicit action to save it (i.e. star it). This works well for my mail, since I receive a lot of mail that doesn't need any response.
Of course, [(label:inbox label:unread) OR label:star], or even its shortened form [(l:^i l:^u)|l:^t] is too much to type all the time. Mihai has a greasemonkey script that can add links for your favorite searches below the labels box, but it slows things down (or at least it used to), and it's a two-step process to perform your saved search when you're not already in gmail.
I've written a simple tool to generate bookmarks that will perform gmail searches. These bookmarks will work even if you're not currently in gmail, but if you're already in gmail it will use your current session instead of reloading everything. I've been using these bookmarks for a while now and I'm happy with them, so I figured it's time to share them with the world.