Sideline is a Twitter app for Adobe AIR built with YUI. With it you can create custom queries and group them by topics of interest.

img http://img.skitch.com/20090402-te2qnxwwj7y7ws21ye5qgwtj9f.png http://sideline.yahoo.com

It’s open source and released under the BSD license. Looks slick!

http://github.com/cauld/sideline