iH8sn0w (one of the more prominent iOS hackers) has released a new tool to help alleviate the pain of leaving a jailbroken firmware. It’s fairly complicated to explain, but it is useful in that it stores the blobs directly on your device. Compared to programs like tinyumbrella and Cydia’s own blob storing functionality, this one is not time constrained by Apple’s servers. This is definitely one more tool to put in the jailbreak toolbox, as it can enable you to jump back to older version of iOS.
Considering that iOS 5 is just around the corner, this will be especially important: iOS 5 may offer plenty of features, but also much slower performance than iOS 4.x. Users of older devices might want to jailbreak and use this just to have the backup of the blobs on hand, in case the performance issue is worse than expected.
This has previously gone by the mysterious codename of Project iF, and was cryptically discussed by iH8sn0w on his Twitter account in the past.
You can download it for Windows here, and a Mac version is on the way. It should work on every device that isn’t the iPad 2, as it utilizes the same exploit that the current crop of jailbreak tools do.