Glest has carried the accolade of being a leading open source game due to the relatively polished nature of it's graphics at the time of release a few years ago. Since then, sadly, the development pace has not matched the original hype surrounding the game.
For the first time in quite a while, there's a major development push. This time, the emphasis is on making it multiplayer.
There's a windows binary patch, and the code is in SVN for other OS users, although is largely untested on anything other than Windows.
Also released today was Star Ship Troopers: Last Defense 2, a mod for Glest. Updated models can be seen in this thread. The download is a whopping 130mb so there's plenty of new content to chew over in there.
That's a lot of Glest goodness. Enjoy!