1. Nature Lovin' SUVs

S. David Freeman, the former head of California's Power Authority, wants to help Gov. Arnold Schwarzenegger keep a campaign promise to retrofit his Hummer with a hydrogen-fuel engine. Freeman, 77, recently signed on with the Hydrogen Car Co., which is launching a fleet of vehicles that run on H fuel made using electricity and water.

2. Play Bach, Boost Sales

Restaurant patrons serenaded with classical music spend 10% more than those grooving to pop singers like Britney Spears, according to a study by the U.K.'s University of Leicester. Classical music makes people feel affluent, says co-author Dr. Adrian North, spurring them to splurge on menu items such as appetizers, coffee, and dessert. Results were consistent whether the venue was an upscale bistro or a university cafeteria.

3. A Sweetener That's Safe

A low-cal sugar alternative called tagatose, recently approved by the FDA, is now sweetening Diet Pepsi Slurpees in 7-Elevens nationwide. Dr. Gilbert Levin discovered the naturally occurring substance while working for NASA back in 1968. Tagatose tastes like regular table sugar but has one-quarter the calories and doesn't cause tooth decay. And, Levin boasts, "this is the only low-cal sweetener I know of that never killed a rat in testing."

4. An eBay of Workers

Seconding.net allows engineering companies with idle workers to lend them to rivals rather than lay them off. Denver entrepreneur Will Smith named his site after the old British military practice of swapping soldiers among units. Companies that borrow workers on the site pay their hourly wages; the main employers still cover benefits. The idea, says Smith, could fly in any industry that has lulls in its workload.

5. Ensuring More Legroom on Your Next Flight

Relief from the jerk on the plane who reclines all the way back in his chair now comes in the form of a pair of plastic blocks, which attach to the tray table, wedging the seat in front in an upright position. Ira Goldman, who is 6-foot-3, began selling the Knee Defender on a website last fall; he sold more than 1,000 in a month, without advertising. Some airlines fear the $14.95 blocks will damage seats and prompt quarrels--Northwest banned them, to Goldman's scorn. "When you buy coach, you're subject to being assaulted by a seat," he scoffs. "And I'm causing air rage?"

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