This handy DIY laser pointer communicator requires little more than time, an old laser pointer, some parts from your local RadioShack, and, of course, a tuxedo.
Here's the PDF file (eyes only!) you'll need to get started on what actually sounds like a pretty neat little 15-minute project.
Basically, the audio signal from the attached microphone varies the power output of the laser. This, in turn, causes the laser's brightness to fluctuate in a way that follows the shape of the sound wave.
At the other end, where your super spy friend awaits his kill order for those pesky neighborhood revolutionaries, a solar cell (or photo-resistor) helpfully converts the oscillating light signal back into the husky, absurdly fake Scottish accent you've applied to your voice in yet another lame, cliched attempt to mimic Sean Connery. [MAKE]