I would like to know how to create an extremely bright spot light, which could be ran on relatively low power.My idea is to make an outdoor art sculpture that will project a beam of light straight up into the sky, bright enough to be seen from a distance. I would like to assemble an array of lights to form a circle (perhaps a 4ft. dia.) with an open center that would be mounted maybe 10 ft. above the ground so people could walk under an look up through the lights. Obviously there would be nothing to see other than sky, but I like the idea of seeing a beam of light from a long ways away and to be able to look up through that beam.The sculputure would only be on display for a couple of weeks and would only need to be powered for a few hours each night. Also, I would really like for the lights to powered (or at least supplemented) by solar panels with a large bank of batteries.Any ideas on how I could achieve this? LED's ? Halogens? What about gas lamps?