Ludicrous speed on a racetrack might terrify most civilians, but the thing that gets Hunter-Reay worked up is a good underwater wreck dive. "There's something spooky about being down there in a wreck," the adrenaline junky explains. "It gets everything going, for sure." One of his favorite wrecks is the Mercedes, a 198-foot freighter that lies in 100 feet of water just off the coast of his native Fort Lauderdale. Hunter-Reay says he uses a combination of nitrogen and oxygen dubbed "nitrox" to prolong his dives.