I've taken the plunge and setup a radio station at Live365.com... It can be listen to over a high speed internet connections and via iTunes, Winamp or any player that can handle an mp3 stream.
Radio Kosmo Sorry about the banner ads and inserted commercials... Live365 is one of a very few sites which allow people to broadcast on the internet legally. From what I can tell there are only a couple quick ads an hour and most of those are for Live365 itself.
I'm not sold on listeners signing up for the VIP program, in part because if my stream takes off ultimately I'd like to move it to swcast.net. Swcast right now is more expensive proposition but with much more flexibility.
Can't wait until Wi-Fi Radio takes off...