Chicago hackerspace Pumping Station: One uses BeagleBone Black to control door access:
There is BeagleBone Black on the Front Door and the Back Door:
The BeagleBone is a connected to a Sparkfun USB RFID breakout with a ID-12 RFID Reader. This scans the RFID keys:
PS1 president Derek Bever and other members are collaborating on this GitHub repo:
Client-side RFID authentication (and general access control)
This system is built on a BeagleBone Black and Sparkfun's USB board for RFID readers for hardware, and PS1Auth's server-side RFID authentication on the backend.
Client-side software is written in Go.