Downgrade iPhone 4, 3GS, iPod Touch, iOS 6 to 5.1.1

A few weeks ago Apple stopped signing the 5.1.1 firmware for devices making it impossible to downgrade newer iPhones, and iPads. Currently the only method to downgrade requires an exploit witch is only available for the iPod Touch 4th generation, iPhone 3GS, and iPhone 4. All other devices can not be downgraded as of now.