How to Add third party apps to your iPhone or iPod Touch by jailbreaking
Jailbreaking your iPod or iPhone is method of hacking the device so you can then download third party apps onto the phone. This will void your Apple warranty, but if that doesn't bother you, here's how to do it. Make sure you back up your device before trying to jailbreak it! This video also shows you how to reverse a jailbreak.