|CTF, a slice of DM and a dash of experimenting. Top pick for simple experimentation alone is a cell-shaded Proball/CTF release. If that does not grab you, check out some tight, fast, vertical action in Hastenpu from Takkie.
Quake 3 releases:
* Floating Stonefaces by sst13 (Proball/CTF/DM 2-6 player)
* Hastenpu by Takkie (DM/Tourney 2-4 player)
* The Proving Grounds CTF by sst13 (CTF/TeamArena/TeamDM 4-8 player)
* sgdtt5 by Deathhead The Tormentor (CTF 6-8 player)
From the Doom 3 side of things we a Co-Op mod called... OpenCoop. More info on the Doom 3 ..::LvL site.
A small bit of trivia, it has been just over a year since a custom Team Arena map has been listed.
..::LvL - http://lvlworld.com/