Unreal Tournament’s #weeklybuilds are now #available to anyone, not just developers.
You may recall these builds popping up back in August, but this is the first time they’ve been made available to anybody with an email address rather than just developers. You can access them through the pre-alpha build thread.
According to games.on.net, builds are available for Linux, Mac and 32-bit and 64-bit Windows, and there are even server builds available. The download is about 1 GB.