The Firefox extension that adds a smart keyboard interface to Firefox—Ubiquity—now supports bookmarklets. Developer Aza Raskin describes, step by step in the video above, how to set them up. In short, you can add any bookmarklet to Ubiquity's command set, and invoke the Ubiquity prompt to execute them from anywhere using only your keyboard. Of course, you can do something similar (but not as good-looking) using Firefox keyword bookmarks, too. Still, Ubiquity has that lovely Quicksilver/Launchy-like suggest-as-you-type command window going on.