Now that Ubuntu can manage my iPod Touch, I was not satisfied with the stock icon.
This package contains clean and colorful icons for iPod Touch and iPhones.
Just extract it somewhere and right click on your iPhone/iPod on the desktop to open the Properties dialog. Click the ugly default icon and replace with the one you just extracted. Close and you're done.
To make it even better, you can right click on the iPhone/iPod icon and chose "Resize icon" to make it a little larger.