Adjustable Raspberry Pi Zero case with Raspberry Pi camera mounted under the bed of CR10. There's two camera version: one with a fixed mount and one with the ball joint. You need some M3 nuts here.

Remixed from the following sources:

http://www.thingiverse.com/thing:1646474
http://www.thingiverse.com/thing:1167846
http://www.thingiverse.com/thing:1436055

Update (2017/04/11) : as pointed out by prankard, I had the wrong cover attached. Updated with the correct one.