Just came to know about this cool App ! It Allows you to switch firmwares with just a touch!
Actually it doesnt change the firmware (Which is Obvious ). It just changes the String of the version in the system file and displays the new version. But, its pretty cool If you need to install apps which dont install after checking the firmware version...
Here are some screenshots:
Checkout the review on my Blog: http://theifoneblog.blogspot.com
Heres the Repo: http://iappcat.com/r/7677