Trac: enhanced wiki and issue tracking system
I love writing about projects that I really like. When I do I try not to write about projects that people may know about and I definitely do not write about projects that come pre installed with Ubuntu. I love open office but it comes pre installed Ubuntu. Trac however does not come pre installed with Ubuntu. There are many solutions out there like trac, sourceforge, google code, launchpad, all of these solutions however are aimed at open source code you publish on the internet. Trac, however lets you host your own website, either on the web or your intranet. That provides a lot of the same features that are provide by the options for open source projects.
The other big option I have seen to trac is dr project (they actualy forked from trac). and while I do like a lot of the things that trac is doing (mailing list intergration for one). Trac has a large comunity and may plugins a few of the plugins I would really like to see in the future for trac are a karma like system similar to the one on launchpad as well as better user tracking as well as a way to see who has read what similar to vbullitins who has read a thread.
Trac really is a great solution and I use for a ton of projects I work on.
Keep up the great work guys!
Edit Typos 
What is Ubunut? Some kind of Mark-flavoured candy? Perhaps you meant Ubuntu?
I switched from trac to redmine a while ago. Take a look, you might like it:)
I was just about to link-drop Redmine as well when I saw inful’s comment. I really find Redmine leaps and bounds better then Trac.
Ok one of the best things about bloging about sw that I like is all the other sw people tell me about. I will be taking a look at redmine for sure.