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A notebook that can run for 10 hours--or longer--before it needs rejuicing? That's the promise of a new battery technology called direct methanol fuel cells. A potential successor to the rechargeable and disposable batteries that power many of today's mobile digital devices, DMFCs generate power by mixing methanol with air and water.

One catch: Most companies are still figuring out how to maximize the power DMFCs provide. Inside the fuel cell, water and methanol must be separated from the catalyst by a membrane. The higher the ratio of methanol to water is, the more powerful the DMFC (and the smaller it becomes).

Also undecided: whether to make the new DMFCs disposable or rechargeable.

Manufacturer Samsung recently displayed a DMFC prototype for notebooks. NEC is also working on one for portable PCs, and Hitachi has plans to sell one for powering PDAs. But don't ditch your existing batteries just yet: Though NEC says it expects to ship its product by year's end, most companies are targeting 2005--and it may be years before the new DMFC technology becomes widespread.

Liane Cassavoy

Price Check: Plasma Prices Plummet

Maybe now you can talk your spouse into a big plasma TV. From November to May, overall prices for plasma fell 21 percent, according to PC World partner PriceGrabber.com. Meanwhile, big-screen rear-projection TV (RPTV) prices dropped 12 percent, and LCD-TV prices fell about 7 percent. We looked at popular models in all three categories (see below; all data from PriceGrabber.com), and found that most closely followed the pricing patterns of their group.

Ramon McLeod