One word, SENA
advrider.com has a good discount for advriders
I cannot rave enough about this system. Me and Kyle used it to great effect on our trip on the BRP. You can charge via a cigarette plug while you use it. It's loud enough for sane speed use. It's just a great all around system and cheap too.
I use it with Andrea and by myself (mp3 and GPS) all the time too.
http://www.twowheelfix.com/showthrea...highlight=sena