The video starts out with a person holding an iPhone. The narrator begins to say he is about to demonstrate how to jailbreak an iPhone. Step one is to update or restore the iPhone to 3.1.2 using iTunes. After the update is complete, click on the blackrain icon and download Cydia. After the download is complete, the iPhone is jailbroken on 3.1.2. Next click on Cydia icon and search for the package bootneuter. That application will unlock the iPhone after installed. After it is installed, make sure unlock says on. Then tap on flash. After Bootneuter has unlocked the iPhone, install the SIM card and restart the phone. The phone then will say t-mobile at the top on the screen.
Oh... and if you're working from home these days, be sure to check out Gadget Hacks' Working-From-Home Essentials.