As for Crysis, Sannyassi nailed it. In fact, they limited C4 to 1 for nanosuits in Crysis Wars since everyone liked to spam it. I don't think it had to do with server load. You could essentially put down 100 or more C4's if you were patient and ontop of a respawn truck or near a spawn area. I remember some admins that would layer an entire floor of a tunnel with C4. It was quite spectacular when it went off. Seeing a wave of explosions come down a tunnel at you made you shit your pants. You'll even see some players put 2-5 C4's onto their trucks/jeeps and ram them into tanks, effectively becoming kamikaze pilots. Altho I have no vid of it, I did manage to hit (and detonate) my truck on a low flying VTOL that was hovering around the Proto/War factorty via the ramp in front of the wall. What a nub! XD