The new service, called Office 365, is available as a limited test from Tuesday, and will be on sale on a subscription basis worldwide next year.

Combining some of Microsoft's existing cloud-based services, it will be available through most browsers and on mobile devices.

That means customers can get access to Office programs like Outlook e-mail and SharePoint websites without installing software, from virtually anywhere.

The move strikes a blow against rival Google, which has had some success with its Google Apps service, which provides a low-cost, Web-based alternative to Microsoft's traditional Office software.

Shares of Microsoft were down 2.7 percent at $25.12 in morning trading, while Google fell 1.1 percent to $610.95.

More: http://www.reuters.com/article/idUSTRE69H4Z320101019

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