Stop acting like children, if you don't know the answer don't post! Maybe he has problems getting punkbuster to work, did you ever think of that? Almost all multiplayer games will have some kind of "hacking" protecting so if its not punkbuster it will be something else.
To the OP,
The only game that I can think of from the top of my head is Tribes, it's an old game but lots of people still play it. Also css doesnt use punkbuster.