I have a few renderings for the iPod Touch (4th generation) case. Essentially there are (currently) two ideas. The first surrounds the camera lens with a depression that fits an 8-tooth Tecnic gear. (Yes, the depression is the same size as an actual Tecnic gear, so it will fit inside the hole.)
The second is a minifig face. The two renderings here show the face with, and without an 'outline' to set it off from the rest of the case.
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