I often see ModMics and Zalman clipon mics recommended for gamers (along with good quality headphones, check this link if your shopping around for a good one which can be priced anywhere from $40 to $1000: http://www.head-fi.org/a/head-fi-buying-guide-over-ear-headp…).
Note that this is the 'mute' version (more expensive), there's a cheaper version that comes without a mute button.
I personally don't need this (I have a zalman) but maybe someone else does so I'll just post a part of what they got on their page below:
What exactly is the ModMic?
Glad you asked! It's a high-sensitivity, steel-spined boom mic with an in-line mute button. Simply attach one of the 3M-pad backed adhesive bases to your favorite headset, and then snap the ModMic into place. Boom! Instant gaming headset!
It's so simple to set up, even a kobold could do it. The ModMic also comes with extra bases, so you can use it with multiple headsets. It's a perfect solution for gamers on the go, an it even comes with a troll-proof carrying case.
Contents:
- One ModMic (with mute button)
- Two base clasps, one top clasp with cap
- One extra 3M pad for re-attachment of base clasp
- One foam pop filter
- Alcohol wipe
- Instructions
- Carrying case
Equip this with the ath-ad900x and you are good to go!