Laser Trip Wire (inspired by: afrotechmods.com) First, it's the "Where's Waldo?" of electronics. "The resistors I need are in there somewhere!" A fine example of how not to load up a breadboard -- I didn't feel like cutting jumper wire, and I can't justify paying for it either. It's like a little electronic city, or bug. Or city being taken over by a bug. Some additional parts: Mirrors, Poster stuff (for applying the mirrors), and an infrared thermometer -- if it didn't appear to be working, I could check to see if the MOSFET was about to release it's magic smoke. And don't forget the all important laser: And there you have it, Laser Trip Wire: In short, while the laser hits the photo-resistor, the LED is off. Once the laser is blocked, the LED will turn on. --The LED can be replaced with pretty much any additional electronics such as: motor control, solinoids, igniters, alarms, appliances, lighting, cameras or even interface with a computer to further expand possibilities with creative programming. Images, and text HTML (c) 2010 The Timmy. All rights reserved.