go here for the plans:
http://www.i-hacked.com/content/view/176/44/
Even thought its IR and you can't see it with the naked eye, you can see IR signals with a digital camera(try it with you tv remote and your camera phone) and most traffic lights with the IR sensor also have camera setups right next to it, so they can monitor emergency vehicles in action, so if you do have this device you will stick out like a sore thumb, But when I read this back in july I thought about maybe installing the IR transmitter in my headlights and when I need to use it, turn my headlights on (daytime running lights) first, then switch the device on, unfortunitly before I decided to make this unit I drove around town to see if I could find actual traffic lights in my arear that this could work on. Well, there are none

plus its a federal offense now! So is it really worth it? Just leave the house 5-10 mins earlier! Still would be fun to mess with traffic though