I think every one of you ever been to an amusement park and ride on a roller coaster. Agree to race at breakneck speed along the intertwining rails - not for the faint of heart. More peaceful invention - a toy that simulates a roller coaster. Instead of iron booths - metal ball, and the variation weaves toy rails can think for himself. For sale this toy at Think Geek for $ 59.99. Video of the gadget in action, see below.