Here's my setup:
The headset is an Otto Breeze that Bigmatty found on Ebay for $10. Very lightweight but stays in place incredibly well. The drop cord and wiring are from a $25 Radio Shack headset. The little box in the middle has a PTT, volume knob, 2 VOX or regular setting, and an external audio input, and runs from a single AAA battery. My MP3 player is wired in so I can listen to tunes while I'm killing. It auto attenuates when the radio is receiving.
The Icom radio has since been swapped out for an Abel 378 (Kenwood clone). I like this radio a ton, and bought a pair after I tried Batman's from BCAC. The thing is great, programmable through the front panel or by computer interface, and the frequency range it covers is unmatched.