only thing is u need a mac and your 3.1.2 shsh saved
There is finally a jailbreak for iPhone 3G, iPod Touch 3G, and iPod Touch 2G MC on the Mac. It is called Pneumonia created by @GreySyntax and @GRMrGecko. It is a Tethered jailbreak which means that you’ll need to use the application on your computer to boot your iDevice, you need to have iOS 3.1.2 to jailbreak, and this requires 10.4 or later
iOS 4.0 – Tethered – New Bootrom Jailbreak « expl0it
There is finally a jailbreak for iPhone 3G
iOS 4.0 – Tethered – New Bootrom Jailbreak « expl0it