BBtv has a good episode on very simple Iphone Jailbreaking.  Damien Stolarz says “It started out very complicated, but these days uh… if you’ve ever heard of a script kiddie, uh… hacking your iphone has gotten to script kiddie simplicity”

It turns out that with the click of a mouse using an application on a computer you have connected your iphone to you too can unlock your iphone.  The application you’ll need is called iLiberty+