This project was inspired by James, who was inspired by Dave from EEVBLOG:
https://www.eevblog.com/2016/04/22/eevblog-871-find-aliens-with-your-raspberry-pi/

It’s a lasercut rack to hold all the Raspberry Pis I could get and make them do distributed computing. (Rather than the standard application for a raspberry pi, which is to sit unused on your shelf)

I was able to find four spare pis at home (see?), and scrounged up another couple from friends. The tricky part was making a caddy that could hold all of the different models (some of which lack screw holes) and allow for easy removal, and also making sure all the connectors were exposed while in the rack.

A network switch is bolted to the back, which avoids too much mess with cables. There’s a separate power switch for each unit, so that the whole cluster doesn’t have to be taken down to change one board.

After playing around with spreadsheets and running some tests, I’m of the opinion that this cluster running all year couldn’t match my macbook running full tilt for a few weeks. However per watt it’s actually not that bad. Dave goes into the numbers much more. 

Files are up on Thingiverse if anyone wants to make their own:

http://www.thingiverse.com/thing:1566301