The Wiimote’s fantastic design makes it useful for a lot of weird projects, like this one by Martin Raynsford.
He’s using the Wiimote’s built-in infrared camera to control the laser in a laser cutter. It’s a funny little hack (via Hackaday), proving that a fishing rod isn’t the weirdest thing that could have a Wiimote attached to it.
The Nintendo Wii Remote has an optical camera in it that is used to detect up to four points of infrared light. The hardware automatically identifies these points and feeds back XY positions through a bluetooth connection. The cutting laser on a laser cutter is an infrared beam, as it cuts through the surface of the material there is a moment where it is reflected off the material and the Wiimote is able to detect the location of the cut. The location data is fed back to a laptop and by comparing this point against the initial ‘in focus’ point we’re able to detect if the Z axis needs to move up or down and by how much.