Real-time location tracker for finding people via RFID fob movements.
Moving into a new building where the working area would be spread out over 6 floors, there was a need to be able to find people easily and quickly. Fortunately, the building security system ensured that all employees carried an RFID fob to unlock the doors on each floor. I took the feed from the security system and wrote a service to parse and update each person's location on a local rails instance.
Each year for April Fools, I substituted out each employee's image for a pop culture character; guessing who was who (and why!) was a lot of fun.