RedMine is a hosting solution for Open projects conceptually similar to Trac. At first sight, the main difference with trac is that redmine is multi-project, while trac has a narrower vision where each trac instance is a project. To be fair there are extensions in trac to administer multiple projects at once, built this is not shipped with the system.
It’s written in ruby. This is not a problem per-se, but since I never worked with Rails, it took a bit more then necessary to get it going. In the end, I configure redmine to run as a cgi as I didn’t manage to get the fast-cgi interface going. The problem is mostly related with apache. It’s fairly slow in this way, but this is by design.
I’ve used Rails 2.0 shipped with debian unstable on a stable machine. The installation was painless as rails doesn’t have conflicting dependencies.
I’ve to play with it a bit more, but it seems a good system , somehow better then trac if you want to have a forge-style site without installing gforge itself.