Received a Pi Rack board as part of the Connect Four Challenge. I consider it the second most useful Raspberry Pi daughter board that I have, just under the RaZberry daugther board. Before having the Pi Rack, I needed two Raspberry Pis, one to host the PiFace daughter board (to sense the push buttons) and one to host the RaZberry daughter board, to control office lights via Z-wave. With the PiRack, the entire design can run on a single Pi and there's room to add two more daughter boards (I'm thinking of adding an infrared transceiver to control the big floor fan).
It does have it's drawbacks though:
- It's a long board that mounts at a 90 degree angle to the Pi. I'm not sure that any known Raspberry Pi case fits around it.
- If you're going to use it for any length of time, you'll need to come up with some way to mount or brace it. If you don't, you'll more than likely damage the Pi's GPIO header/pins or crack a few solder joints.
- The docs could stand some improvement. I got the impression that the described jumper settings were actually the opposite of what were needed (i.e., I had to change them to get my project to work).
All in all, it's well worth the $11 price.