You may have seen the Ambient Orb
on ThinkGeek or similar sites. Admittedly, it is a cool device, but quite expensive, and its appearance is not quite that high up on the "cool" scale. So, in the same vein of relaying information in simple terms, this hack came to be.
The idea first came to be after reading this page.
Okay, cool, you can light up LEDs with 5 volts DC, but 100 watts of 125 volts AC is a completely different animal. When I received this traffic light for my birthday (purchased at a flea market for ten bucks), I jumped right to it.
Going into this project, I'll admit that I had virtually no electronics knowledge whatsoever. However, after hours of toying with this project, being frustrated, and then finding help from people online, I can now safely say that I learned absolutely nothing in that time.