iFuntastic

iFuntastic is the ultimate customization tool for the iPhone and iPod Touch. Its main feature is the ability to modify the interface's appearance on these devices.

iFuntastic is compatible with Winterboard templates, so it's possible to apply different styles easily and quickly. The main changes supported by these templates are the ability to set a slideshow, a sequence of videos, or a panoramic picture as your background; change the icons and names of applications; change the lock screen; and so on.

It can also be used to copy notes, text messages, and voice messages stored on the iPhone's memory to your computer's hard drive.

With iFuntastic, you can also transfer or remove files from the device, copy the iTunes library, add and edit ringtones (cut, adjust volume, and add fades), take screenshots, apply backgrounds, rearrange icons, create custom email signatures, and much more. 

Note: For Mac OS X 10.4 or later. It requires firmware 2.1, 2.2, or 2.2.1.