Is Quora the Next Red-Hot Web Start-Up?
This Q&A service is one part Twitter, one part Wikipedia—and if you ask a question, you might be surprised by who shows up to answer it.
Melody: Community Powered Publishing
An alternative to Movable Type 4
20x200
(limited editions × low prices) + the internet = art for everyone
Open Atrium
Intranet, open source, built on Drupal with some nifty features. Looks nice too.