I got an Arduino Uno for Christmas last year, and of course the first thing I think of is laser pointer turret. I played with this for months while I learned the basics of Arduino programming. It was knocked apart when hail totaled my Trailblazer.
To simplify rebuilding the turret, I bought a pan/tilt kit from trossen robotics. I upgraded the laser from a wal-mart cheapo with the buttons taped. Aixiz lasers are inexpensive and very easy to use. The aluminum mount is taped to the pan tilt kit.
http://www.trossenrobotics.com/store/p/3139-Pan-and-Tilt-Kit-with-Servos.aspx
650nm 5mW laser module.3.2V 12x30mm
http://www.aixiz.com/store/product_info.php/cPath/59/products_id/302
12X30mm aluminum mount for AixiZ 12X30mm units
http://www.aixiz.com/store/product_info.php/cPath/28/products_id/99
I actually bought my laser parts through eBay
http://stores.ebay.com/aixizserviceandinternationalllc
The arduino and radio shack project boards are housed in a plastic bin I bought from wal-mart for a couple bucks. I hung it on the wall with a piece of decorative ribbon swiped from my girlfriend’s wrapping bin. I wanted to see the cats attacking the laser, so I dug out my webcam.
Hanging from the wall in place of a picture.
pan tilt servo kit
2 mp autofocus webcam I got on eBay for like $15
And of course they fall asleep when I’m ready to test it.
Raging Computer 