In the old movies, a little sliding door would open so the doorman could check you out and let you in. With [IsmailSan’s] electronic lock, the secret knock automatically unlocks the door.

[Rob Hemsley] sent in an update to an RFID-based door lock. Previously, if you wanted to enter the MIT media lab, a RFID-enabled card was required to get in. Now, with [Rob]’s update, you only ...