Id say a mic would work, but......... A HEADSET IS SO MUCH COOLER, I MEAN, ITS A HEADSET, COMMON DUDE! not a crappy headset, like a 60 buck headset that wraps around your ears, not the crappy little disks that slide down your face when you try to put them on.
there is also ventrillo, it doesnt make you lag when you try to sign on. but other people would have to be connected to that same server IP address. this is the same with TS
I know, I had Ventrillo, I found that XFire is easyer for me to use with my friends, but thanks anyways.