This is not another useful hack of the Wii (like our post on How To: Wii-mote Control Your Curtains), but it's close. This hack from Instructables user action_owl takes advantage of a CD-Rom drive and an 'eject' command to lock and unlock a sliding bolt...
Once the output from the Controller is read, it sends a signal to eject a CD-Rom Drive which pushes or pulls the lock.
Once activated, NoKES (or NintendO Keyless Entry System) will be blinking letting you know that it is alert and keeping guard. Only a specific combination of buttons will open your door.
If you enter an Incorrect combination, the NoKES plays a fail sound and—get this—snaps a picture of the attempted intruder (or confused drunk friend who wants to play MarioKart) with an attached Webcam. When idle, NoKES will also "listen" for vibrations. If someone knocks on the door, the NoKES will take another picture letting you know who stopped by.
We want somebody to take this wireless with the Wii!