Meh @ clip-on mics... I have a creative boom mic on my desk that has really good sound reproduction, guess i'd probably just stick with that if I'm using a headset. It's annoying using it with speakers though because of the nasty feedback others get.
Another vote for 5.1s being usful as in CS. Ive used llwyds. And playing againsed Llwyd/Jiffz/Dave/Kemp i know i have to be as quiet as possible as they have the advantage, and it DOES show.