This is the case for the Measure the Future sensor, based on a Raspberry Pi 3 Model B and a Logitech HD Webcam C525. There are two different setups for the sensor, one designed to sit on a shelf or ledge, and another designed to hang from a drop ceiling grid with a ball-joint for positioning.
You can mix and match the ceiling mounts as well. There's a Flat ceiling mount that can be screwed into a ceiling or mounted with double-sided mounting squares, or the drop ceiling mount that can be clipped over a ceiling grid.
If you need a different mounting type, please leave a comment and I'll see about adding it, or model it and let me know and I'll add it to the collection.