easy solution to large-player FPS games onlilne: get on voice comms software with your buddies, and play in the same server... it's just like a LAN.
I've been playing with TNT, my TFC clan, since 1999.. we're practically family, though most of us have never met. We know each other so well, however, through our use of voice comm programs like Ventrilo/RW/TeamSpeak. This allows us to laugh and joke just as if we were in the same room together..