Singapore will "spare no effort" to hunt down hackers from activist group Anonymous who last week threatened to wage a cyber war against the government, Prime Minister Lee Hsien Loong said Wednesday.

Lee told reporters the city-state had also strengthened its defenses against such attacks.

Pneumatic muscle suits and a walking stick that behaves like a guide dog competed for attention with an industrial robot that can paint fingernails at a huge expo in Tokyo Thursday.

In a country where a quarter of the 128-million population is aged over 65, innovations that can make life easier for the elderly or their caregivers are potentially big business and the subject of a lot of research.

Google ended nearly two weeks of speculation about an enormous floating barge in San Francisco Bay, saying it would be "an interactive space" for learning about technology.

A Google spokesperson dismissed wild conjecture about the barge, which was spotted last month by the technology news blog CNET, which spurred rumors by calling it a "secret project."

Google on Tuesday launched a new online service called "Helpouts," aiming to connect businesses and consumers to solve problems or get advice on a range of issues.

The service is similar to Google's "Hangouts" with live video for paid services in areas ranging from computer tech support to weight loss.

Samsung Electronics promised to boost shareholder returns as it held its first analysts' briefing in eight years Wednesday in a bid to shore up its flagging stock price.

Samsung President Lee Sang-hoon said the company would "put more emphasis on shareholder return" and would target a dividend yield this year of 1.0 percent of the average share price.

Guatemalan siblings who lost contact during the country's turbulent 1960-1996 civil strife have been reunited 31 years later, with some help from Facebook.

Ofelia, Avilio and Elsira Funez Velasquez had their tearful reunion at the headquarters of the Mutual Support Group, an activist with the social group, Enrique Barrera, said.

Microsoft chief executive Steve Ballmer on Tuesday said the computer giant had to reinvent itself to avoid being "old and tired" as his company struggles to keep up in the mobile devices sector.

"We're finding ourselves having to start up again," Ballmer said at a conference in Rome where he announced Italy had become the first country in which Microsoft phones were outselling iPhones.

A group of Italian computer boffins have launched a new website, Mafialeaks, aimed at encouraging victims of organised crime and former gangsters to spill the beans, La Repubblica newspaper reported Tuesday.

The site will allow people "to denounce mafia activities anonymously, protecting those who supply the information," the daily said, citing one of the creators.

PlayStudios on Tuesday blurred the line between online and real-world gambling with the release of myVegas Slots smartphone games that let players cash in on perks at Sin City casinos.

Free-to-play versions of myVegas Slots released for Apple or Android smartphones let people test their luck on virtual one-armed bandits such as those found in the Mirage, Luxor, New York New York or other MGM Resorts International properties and then use payouts to get VIP treatment in Las Vegas.

The wife of Jeff Bezos is giving a thumbs-down to a recent book about her husband's company, Amazon.com Inc.

On Monday, MacKenzie Bezos posted a one-star review on the Amazon page for Brad Stone's "The Everything Store," which came out last month and has been received positively by critics and Amazon readers. Bezos wrote that the book was filled with inaccuracies and biased against her husband and Amazon. Spokeswoman Sarah Gelman of Seattle-based Amazon confirmed that the review was indeed written by MacKenzie Bezos.