Jailbreaking the iPhone 3G to firmware 3.0.1

• Grab the 3.0 firmware and the 3.0.1 firmware from Felix Bruns.
• Grab the latest redsn0w version from the dev-team.
• Fire up iTunes and update or restore your iPhone firmware to 3.0.1 by shift-clicking (Windows) or Option-clicking (Mac)
• Exit iTunes
• Fire up redsn0w
• When redsn0w asks you to identify the IPSW used, point it at the 3.0 IPSW instead of the 3.0.1 one
• Follow the instructions on screen and wait for the jailbreak to complete.
  If redsn0w appears to be 'hanging' while waiting for the iPhone to reboot, then unplug your phone, wait 3 seconds, plug it back in. The installation will now continue.
• For the unlock, start Cydia on your iPhone, add repo666.ultrasn0w.com as a repository, install ultrasn0w
• Done.