Another project with the kids: I hopped up the track by mounting it to a board and 'foaming' a landscape with "Great Stuff" expanding spray insulation. The process is a little messy but the results are good. The racing billboards are Google Images downloaded graphics, printed in Word on photo paper and laminated. The traffic light works- scavenged from an old battery operated water fountain LED setup, and LED flex-neck pocket flashlights make good streetlights for the track. I've invited the kids to paint the landscape to mimic a desert or jungle. Initially this Disney-Pixar 'Cars' track was powered by 4 D-cell batteries, but we've switched it out to an AFX Tri-Power AC adaptor providing 8, 12 or 22 Volts. The kids love it, and the cars really haul now. A little steel wool polishing on the track cleans up the oxidation on the rails after it's been unused for a bit. Note the tunnels under the track. I glued down empty cardboard tubes before foaming so Ben could use his HotWheels cars on the same board. It was a fun project and the kids learned a lot about electricity doing it. I did spend way too much time on this though and obsessed a bit over it. I'm glad it's done!