Chicago hackerspace Pumping Station: One uses BeagleBoard 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:


[More photos]


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.