Manufacturer, MojoWijo (which has also released a baffling and weirdly SFW promotional video) has this to say:
The device is attached to the accessory port on a Nintendo Wii* remote control. The control is then connected to a bluetooth enabled PC running Mojowijo software. Using Mojowijo’s patent pending Motion2Vibration technology, the device is able to transform the varying motions of the control into appropriate vibration signals and send them to another selected device – in the same room or over the internet. (Wii gaming console NOT required). Essentially turning your Wii remotes into shared, remote controlled vibrators (aka wii vibrator or wiibrator!)
Can’t sleep. Claw’s gonna get me. Can’t sleep. Claw’s gonna get me.
UPDATE: They’re doing beta-testing! Run!