The track at Denver Indoor Kart Racing isn't one of those wussy kids' tracks with accelerator regulators and lanes that are too narrow to pass in. This is the real deal -- and worth the hunt to find the obscure warehouse just north of I-70. Helmets are required -- yes, the carts can spin out -- but the front desk sells head socks so you don't have to swap sweat with strangers. For first-timers, a good trip around the quarter-mile track is 27 seconds, but pros can whittle it down to a mere 21 seconds. Anyone taller than 4' 8" can drive the adult cars, but the year-and-a-half-old facility also has a corral of junior carts on hand so that the whole family can compete against each other. Gentlemen, start your engines.