GoPro Hero 3+ lens cap and power button cover
Lens cap and power button cover for the new GoPro Hero 3+. I printed this in ABS. It fits pretty snugly, your mileage may vary based on material shrink/expansion during printing.
Update: I added a new version with some refinements, including a tapered interior for a better fit, and some filleting around the underside of the cap rim (look for the v3 version)