Thousands of smartphones pass through New York City's Herald Square each day, but few tower higher than a few inches, or run Windows Phone 7.5. In celebration of three new Windows Phones hitting stores -- the Samsung Focus S, Focus Flash and HTC Radar 4G -- Microsoft has constructed a monstrous six-story "Windows Phone" just a few feet away from the world's largest Macy's store, right in the middle of one of the city's more popular outdoor picnic areas. The gadget sure is huge, but it's not a phone in the traditional sense -- enormous tiles display video feeds transmitted from a control room, and move out of place to accommodate live stage performances. We dropped by for a midday calisthenics session, which surprisingly appeared to be a hit with locals and tourists. There were functioning devices on hand as well, in a makeshift showroom, though those were far less popular than the 55-foot behemoth front and center. Jump past the break to see it in action.

Microsoft Corp said hackers exploited a previously unknown bug in its Windows operating system to infect computers with the Duqu virus, which some security experts say could be the next big cyber threat.

"We are working diligently to address this issue and will release a security update for customers," Microsoft said on Tuesday in a short statement.

News of Duqu surfaced in October when security software maker Symantec Corp said it had found a mysterious computer virus that contained code similar to Stuxnet, a piece of malicious software believed to have wreaked havoc on Iran's nuclear program.

Government and private investigators around the world are racing to unlock the secret of Duqu, with early analysis suggesting that it was developed by sophisticated hackers to help lay the groundwork for attacks on critical infrastructure such as power plants, oil refineries and pipelines.

Details on how Duqu got onto infected machines emerged for the first time on Tuesday as Microsoft disclosed its link to the infection.

Separately, Symantec researchers said they believe hackers sent the virus to targeted victims via emails with tainted Microsoft Word documents attached.

If a recipient opened the Word document and infected the PC, the attacker could take control of the machine and reach into an organization's network to propagate itself and hunt for data, Symantec researcher Kevin Haley told Reuters.