Twitter Inc

Amazon.com Inc. shut like a book. Domino's Pizza Inc. was late but eventually delivered. And CNN focused on the good news. When the three major brands engaged with their Web-savvy fans and critics in separate incidents last week, their responses demonstrated how corporations are still learning how to control their messages -- and reputations -- in a fast-twitch online world.

The cyber attack that brought down Twitter for several hours Thursday was aimed at a single blogger in the country of Georgia, according to Facebook, which was also targeted in the attack. Cyxymu, as the blogger is known online, uses his blog and accounts on several social media networks to lash out against Russia, which has waged battles with Georgia over disputed territory. "Yesterday's attack appears to be directed at an individual who has a presence on a number of sites," Facebook said in a statement.

Some of the actors on NBC's drama "Heroes" are among those in Hollywood who may have the superpowers to help Twitter break into prime time. Greg Grunberg, who plays a Los Angeles cop with the ability to hear people's thoughts, pulls out his iPhone nearly everywhere, including between takes on the studio lot, to tap out the short Twitter messages known as tweets. He broadcasts them to the more than 20,000 friends and fans following him.

A self-described anarchist from New York City has been accused of sending Twitter messages with the location of police officers so that protesters could evade them during the Group of 20 economic summit in Pittsburgh. Pennsylvania State Police arrested Elliot Madison, alleging he used Twitter to direct the movement of protesters and inform them about law enforcement actions at last month's summit. The New York Post reported the arrest in Saturday editions. Court papers filed by Madison's attorney say that FBI agents executed a search warrant at the 41-year-old's Queens home.

To understand how the wizards of Twitter settled on 140 as the magic number of characters in a single tweet, you have to go back two decades to Bonn, Germany. One day in 1985, Friedhelm Hillebrand sat at the typewriter in his home there, tapping out random sentences and questions on a sheet of paper. As he went along, the communications researcher counted the number of letters, numbers, punctuation marks and spaces on the page. The blurbs nearly always clocked in under 160 characters.

Mark Horvath, a documenter of homelessness who was once homeless himself, was touring a tent city in Sacramento when he raised his cellphone to take a photo of one man's ingenious shopping-cart storage system. Suddenly, another man rushed at him, screaming, with a knife. Horvath was terrified, he said, but not so scared that he stopped sending photos and text messages about what was happening.

You've used the Internet to do research on your new car and to find the value of your old one, and you've visited online fan sites and notice boards to get the most out of your shiny new ride. But have you tracked a new-car launch or auto product on Twitter? Car companies are increasingly using the seemingly ubiquitous Twitter to inform and engage potential and existing customers. But will the bold new experiment in social media work?

Online predators have hit on social media site Twitter as the latest tool to lure victims into get-rich-quick and work-at-home schemes, according to the Better Business Bureau. After tracking years of scams involving e-mail and Google, the bureau is seeing a surge in the number of companies claiming to help people turn Twitter into a virtual ATM with little effort and no risk, said spokeswoman Alison Southwick. "Twitter is the cool thing, the bright, shiny object," she said Monday.

Could this be the first Twitter baby? Twitter Chief Executive Evan Williams and his wife, Sara Williams, just had their first baby, an event shared with more than 16,000 of her Twitter followers from the time her water broke to baby's first diaper. The wildly popular micro-blogging website allows people to send out messages, each at a maximum of 140 characters -- about the length of a major contraction. But through it all, she kept up the tweeting. It started Monday at 8:46 p.m. when she messaged: "Dear Twitter, My water broke.

When you're San Francisco's hottest start-up, you don't need to look for funding. The money comes to you. Twitter Inc. closed a $35-million venture capital round led by Institutional Venture Partners and Benchmark Capital. Co-founder Biz Stone said the micro-blogging service still had money in the bank from two earlier funding rounds, which totaled $20 million, but Twitter received "an offer we couldn't refuse."