I like some of the ideas here, but I think my current browser, Conkeror (not to be confused with Konqueror), has already solved this problem. Similar to the way that Quicksilver for OS X works, I just type at it the buffer (tab) I want and it gets it for me. It would be pretty cool for it to be able figure out what the content was so I could say "camera" and it would find all the camera related stuff though...