Crown's Knife TDM. I liked that he used various slate maps, like that one map with the trees everywhere. That, and it makes me nostalgic.
Fortwars (especially the rare ones that took place on city maps)
Government vs. Rebels servers (on GSF maps; newer one from v21 was pretty good too though)
Any server on a GSF map, since those maps were lots of fun for me back then.