Really simple & cheap light-bar, powered and controlled from pc ( over lpt port ).
It will cost you something about $10-20 to build this
( I had the plexi and lpt cable for free, so I only paid $3 for led torch and $3 for nuts and bolts )
= killer raito fun for money
video in action
video from testing
In real world is even better looking because eyes are slower than digital camera, so it is glowing nicely.