Trying out Extensions in Google Chrome for Mac

The beta version of Google's Chrome browser for Mac finally got support for Extensions (which are essentially little widgets you can install onto the Chrome interface), so naturally, I've been spending a good chunk of the afternoon testing one extension after another. So far, I've seen a series of ad blockers, two or three Facebook extensions, several Gmail checkers, and (of course) an extension that keeps track of your extensions ... so no, nothing life-changing yet. Will keep looking. Got any suggestions?