Jailbreakers and Unlockers - save your iOS 4.2.1 SHSH blobs now!

Apple will soon disable restoring to iOS 4.2.1 for iPad and iPhone. In order to preserve jailbreak and unlock save your SHSH keys now! 4.3b keys might also help you in future untethered jailbreak.

You can do that using TinyUmbrella utility. Download it for Mac or Windows here. Just run it and push "Save ALL SHSHs" button.

The other way is to save SHSHs via Cydia. Run Cydia and make sure the keys are saved (green line on the top).