Looking for some more diverse music on your iPhone or iPod Touch? The Unearthed iPhone application from the ABC's Triple J gives you access to 53,000 tracks from unsigned artists, and neither the app or the music will cost you a cent.
Tracks are downloaded directly within the application. Shaking your phone will produce a suggested random track to listen to, and you can build your own playlist. There's also a streaming option if you don't want to download tracks, though that will chew through your data allowance pretty quickly if you do it on the go. Recommended playlists from Triple J hosts are updated weekly.
One note: while music downloaded into the application remains freely available to play, you have to do so from within the Unearthed app. If you want the tracks in iTunes, you'll need to download them from the Unearthed web site — which is also a useful option for free music if you don't have an iPhone. Unearthed is a free application for iPhone and iPod Touch.
Triple J Unearthed Mobile [iTunes link]