HLDM and maybe TFC are all I'd throw in, I don't really play much else. In other news, there's a free trial of Tribes 3 becoming publically available in one week, and I highly recommend at least trying it out.
If you liked UT2004, you'll definitely like this at least as much. It's not like T2 where it's all slow and annoying. Anyway, I need people to play with in the beta so.. y'know.. keep me company and all that. ;~