Say what you want about Google Instant, but it's got some pretty awesome keyboard shortcuts. Google-centric blog Google Operating System lets us know of one more: Just hit Escape to move back up to the search box and type a new query.
Say you've searched something on Google Instant and hit Enter. If you don't find what you're looking for, there's no reason to grab the mouse and start clicking around—just hit Escape to go back up to the search box, and you can type a new query. Alternatively, if you only want to add terms to your current query, you can just start typing—Google will even add a space for you. Check out the video for a quick demonstration.
Esc to the Rescue [Google Operating System]