A single Facebook message on a congressional election day in 2010 prompted about a third of a million more Americans to cast their vote, scientists said on Wednesday.

The biggest-ever experiment into social networking confirms that peer pressure in cyberspace helps get out the vote in the real world, they said.

Motor racing is set for an electric makeover that will see a new generation of green cars speeding at 220 kmh (138 mph) around urban racetracks -- at least until their batteries run out.

Alejandro Agag, CEO of Formula E Holdings, says the global championship, which has been authorized by motorsport's governing body the Federation Internationale de l'Automobile, will help finally make electric cars popular.

Apple on Wednesday introduced its new iPhone 5, a lighter, thinner and more powerful version of its iconic mobile device.

"It is an absolute jewel. The software and engineering that went into this product is the most challenging our team has ever taken on," Apple marketing chief Phil Schiller told a packed launch event in San Francisco.

Scientists on Wednesday reported they had invented an invisible tag using the widely-used "quick response" code to help thwart banknote forgers and criminals who sell bogus drugs or fake vintage wine.

The QR code is a square of black and white pixels that can be scanned by a smartphone, which then links to an Internet address.

Facebook founder Mark Zuckerberg said Tuesday the social network giant is focused on mobile devices and should be seen as a smart bet despite a "disappointing" stock market debut.

"It is really clear from the stats and my own personal intuition that a lot of energy in the ecosystem is going to mobile, not desktop (computers)," Zuckerberg said during an on-stage interview at a TechCrunch Disrupt conference in San Francisco.

Tech startup BrandBounty on Monday sought to enlist smartphone users around the world in a "crowd-sourced" battle against knock-off goods and pirated digital content.

The creators of BrandBounty, which launched earlier this year, were at a TechCrunch Disrupt gathering of technology startups in San Francisco to show off an application they designed to transform "consumers into brand vigilantes."

Worldwide spending on information technology is expected to grow six percent this year in constant currency, a slight dip from 2011, a research firm said Monday.

International Data Corporation said the growth pace, down from seven percent last year, comes "in spite of continuing macroeconomic uncertainty."

Microsoft said Monday it is launching more than 30 pop-up holiday shops in the United States and Canada as it gears up to sell its new Surface tablet computer.

"Microsoft is excited to expand on its existing retail footprint to deliver an assortment of best-in-class products and a premium retail experience to new locations," the U.S. tech giant said in a statement.

Moody's on Monday cut its credit rating on Japanese consumer electronics giant Panasonic, citing the struggling firm's weak profitability and high debt.

The global agency said it lowered the rating on Panasonic by two notches to Baa1 from A2, while keeping its outlook stable.

Apple becomes the focus of the technology universe Wednesday as the world awaits a new iPhone with a big, beautiful touchscreen and connectivity to blazingly fast telecom networks.

Apple has been tight-lipped about what is in store at its media event in San Francisco, but hinted at a keenly anticipated "iPhone 5" in invitations that bore the cryptic message "It's almost here."