I've just got to say, I've been completely blown away by MovableType, the blog software that drives a lot of Werkenland. It's so clean, intuitive and fun to use. I do have a few complains, with regards to setting up a large number of blogs. I'm not much of a Perl hacker so there may be some perl interface to configure new blogs hiding somewhere that I haven't looked, yet.
Jira, from Atlassian also looks pretty cool, and they have free licenses for open-source software. I know the winds seem to be blowing towards Scarab, but I think I'm going to give Jira a shot. Sure, it's not free for commercial use, but people have to make a dollar every now and again, ya know.