There's a place where nitro fuel drifts over the water like an illicit rumor, where rocket ships the size of fire engines skip across the waves so fast you'd think they were heading back to Mars, where the very earth seems to crackle with supercharged engines. This is the Nitro Nationals Drag Boat Festival, and it's a 3-1/2-hour drive north of San Francisco on Memorial Day weekend. Denizens of S.F. have seen boat races, sure; the bay's lousy every weekend with regatta-going yuppies. But few have seen a boat race where the "track" is a quarter mile and the winner completes it -- destroys it really -- in around five seconds at more than 200 mph. Occasionally one of these sleek vessels will accidentally take air, glide a moment, flip, and stab back into the waves, tumbling like a windblown leaf. Drivers, ensconced in an encapsulated cockpit, don't die, usually. San Franciscans wishing to witness some of this one-of-a-kind action should drive up to Red Bluff, book themselves into the Cinderella Motel -- or the Relax Inn, or the Crystal Motel -- show up the next morning at 6:30 at the Sacramento River near downtown for the official breakfast, then watch an afternoon of motorized profligacy.