I wanted to create a small compact Laser Unit that fitted in as small a footprint as possible. The Laser Module and other electronics fits easily into a standard LEGO '2x4 Brick', with a '2x3 plate' & Technics Connector attached to the bottom. It would have been possible with some effort to fit all the parts within a '2x3 Brick'. I decided on a Fly-lead instead of a standard NXT style Socket to keep the unit compact. The Laser is very bright, despite it's very small size, so as a range-finder the camera can pick it up from a far. Like a NXT Light Sensor's Red LED, the Laser can be toggled on and of via Software.

Details: http://www.rjmcnamara.com/?p=3582