People and organizations are doing a lot of interesting things with Mozilla technologies. Here are two of the many Mozilla-based applications available. If you would like to suggest other applications to feature, please leave a comment.
Buzzbird is a freely available open source Twitter client built for Mac OSX, Windows, and Linux that offers multiple account support, selective filter views, and more.
Sit back and get ready for big-screen browsing. Kylo brings your TV and computer together to create the ultimate content experience. Take your HDTV anywhere on the web.
davidwboswell 
New genome analysis and presentation software – based on xulrunner
Thanks for letting me know about Enlis. I’ve added it to the Mozilla-based apps page.
http://www.mozilla.org/projects/mozilla-based.html