Not that I'm aware of. A non-Jailbreak device is pretty much locked down. I do know, however, you can SSH into the device and make some changes... just not sure what or how to go about it.
you might be able to use an app like iphone explorer and change some of the app store apps icons as it gives you access to those apps folders and you can easily manipulate the files and cheat so changing the icons should in theory also be something you could do, download the app from here: iPhone Explorer - Download
you dont have to be jaolbroken, I am un able to try it atm as I cant get a usb to plug in my iphone