I love my iPhone. Like Mary Poppins, it is practically perfect in every way, but sometimes I find myself wanting to hear music I don't have in my mp3 list (but not willing to pay the 99 cents in iTunes), or struggling to find just the right mix of songs (but setting up a new playlist can be so inconvenient). Just the other day I was wishing there was a way to combine radio with my iPhone. Lo and behold, today I discovered Pandora.
Pandora is a free(!!) service that streams radio over the internet, learns your preferences because it allows you to rate the songs you hear, and now has an app for the iPhone that uses the 3G network! I actually knew about the PC version from several years ago, but live streaming audio takes up a lot of bandwidth so it was quickly exiled to the forbidden list by the firewall people at work.
You download the app to your phone, and then start your own new "station" by giving Pandora a seed song or artist to start from. As songs play, you either rate them "thumbs up" and Pandora adds more music you might like to your station based on that song, or you rate them "thumbs down" and that song is never played again. You can set additional seed songs on that station to get more variety, or start a completely new station for a different type of music.
The tradeoff for free music is a 15 second commercial once every two hours, and an occasional popup banner over the album cover art. Totally worth it to me, but if that bothers you, there is also a paid subscription you can sign up for that will make your iPhone/Pandora experience totally ad-free.
Isn't technology great?