So you have already all you music on your computer but you want to hear it on the mobile.  Some new services are trying to make that happen. They are right now quite clunky, but expect to see many new software tools like this..

However, for now… they don’t seem to be getting too much credit:

Ditty Bot or Ditty Not

Boing Boing and Make are foaming over this thing called Ditty Bot, which is going to let you stream music from your Mac to your cell phone. I wonder if they really considered how ludicrous this whole thing is. Come on - you stream music from your computer using SkypeOut ($$$s) and listening to it over a cellphone connections (more $$$s) and get questionable quality. A data-on-cellphone plan is going to cost $25 a month. At 2 cents a minute, an hour of SkypeOut is going to cost $1.20. Do this an hour a day for 30 days and you have spend about $60. Of course, you could buy a iShuffle for $99, but that would be too simple! And who would want to listen to higher quality of music!

http://gigaom.com/2005/06/17/ditty-what/

http://plasticbugs.com/index.php?p=267