You'd be forgiven for assuming that the future of airships died in 1937 when the Hindenburg exploded in a deadly ball of flames above a New Jersey airfield. While the disaster was certainly a buzz kill for the fledgling blimp-travel industry, dirigibles have, strictly speaking, never been entirely out of fashion (Goodyear, for example, has been continuously flying its famous fleet since 1925). But things are about to get a whole lot more fashionable in the world of giant gas-filled floating transports: Two companies are promising major entries in the "lifestyle zeppelin" class of air travel in the next few years.They are designed for medium-haul flights (like transatlantic crossings) while providing every possible amenity, from spas to casinos, not to mention staterooms that will "rival the luxury cabins of the world's greatest ocean liners." Think of it as Titanic meets Hindenburg-what could go wrong?