Mechanical Laser Show.

[steve001]

Here's a simple handcranked device for creating equally simple patterns.
https://youtu.be/_dtBUiaAqRE

 

[ElectricPlasma]

There was already a thread on this.

http://laserpointerforums.com/f42/ingenious-non-scanner-set-3d-printed-laser-projector-100751.html

 

[CurtisOliver]

Yep, still cool though.

 

[steve001]

I'm always late to the party.