For the Grand Coulee Dam's laser light show, they use 4 large frame Coherent Sabre Lasers - 2 red 12-watt Krypton lasers, and blue and green 30-watt argon lasers. That would probably be too complex to set up for this one publicity stunt.<p><a href="http://en.wikipedia.org/wiki/Laser_light_show_%28Grand_Coulee_Dam%29" rel="nofollow">http://en.wikipedia.org/wiki/Laser_light_show_%28Grand_Coule...</a>