Coincidence, the iPod I'm using right now is jailbroken :P It's as if you're unlocking it, you have tons of features and all that. It's really cool. you can do things like change your font, get free apps if you get the right packages, access free in-app purchases, and SO much more. The only downsides are how if you aren't careful you might really screw up your device, if you call apple for help and you tell them it's jailbroken then they won't help you, and also the warranty will no longer be available. I think Apple has tried to make it officially illegal, but i don't know if they have already.