iSHSHit: Save SHSH On Your iPhone or iPod touch
How to use a saved SHSH blob to downgrade firmware: http://stateofjailbreak.com/tutorials...
In this video I show you how to save your SHSH blobs on your iPhone or iPod touch using iSHSHit. iSHSHit is a free download that allows you to send your SHSH to Cydia as well as email a copy to back up locally on your computer.