Despite the high cost of powering cargo freighters, it doesn't look like viable alternatives are appearing anytime soon. Instead, the enormous ships are increasingly turning to innovative ways of lessening fuel consumption. One promising possibility is massive sails—kites really—that can be retrofitted onto ships and aid in propelling them across the ocean. Earlier this month, Beluga Shipping christened its MV "Beluga SkySails"—a cargo ship with a 520 square foot propulsion kite; the first to utilize the system. A transoceanic voyage is imminent, but unfortunately for PPX buyers, the date has been pushed from mid-December to January. Most traders guessed correctly, however: The SKYSAIL stock (Will the sail-assisted Beluga freighter depart by December 20, 2007?) was halted at $35.75 and closed at $0.—Abby Seiff
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