Pandora is an internet streaming radio service, which suggests songs based upon your tastes and the like, a lot like Last.fm, but without requiring registration or the like. It's a service that is perfectly matched to internet capable portable devices; allowing you to listen to a mass variety of tunes without having to store them all on the limited capacity of the phone or device. This is why I am very much a happy man that the new iPhone App store does indeed have a Pandora application for your listening pleasure.

Unfortunatly Pandora is only avaliable in the US due to licencing issues; namely the idiotic costs the RIAA puts on radio royalties.... shame.

Still, worth checking out if you are a US iPhone owner.