Rocks in the Paper Shell - Neotokyo.
Neotokyo was recently updated. Neotokyo is a class based CTF game with an emphasis over positioning and tactical stuff over shooting (the shooting mechanics are rather simplistic, but there are no directional indicators when hit, so getting the drop on someone is much more vital then reflexes). Also: The flag can be used as a radar. Using your mic is vital.
The game is build on the source engine, and requires source SDK Base 2006 to run (everyone should be able to acces it at this point).
Here is an overview on how the game is played.
I plan on playing this game with you guys - I do, however, have no idea yet where and when. Any suggestions?