so last night a new jailbreak has been released which basically jailbreaks your iphone over the net (safari) without needing a PC or MAC.

http://www.iphonehacks.com/2010/08/j...a-mobile-.html

works on all iphone models.

Go to either:

http://jailbreakme.modmyi.com/

or

http://www.jailbreakme.com/

on your iphone