Microsoft today announced the public beta of Microsoft Office 365, the company's next-generation cloud productivity service for businesses of all sizes.

Office 365 was recently introduced in limited beta, bringing together Microsoft Office, SharePoint Online, Exchange Online and Lync Online in an always-up-to-date cloud service.

Microsoft Office 365 is a subscription service that combines Microsoft Office Web Apps with a set of web-enabled tools. Office 365 brings together Microsoft Office, SharePoint Online, Exchange Online and Lync Online in an always-up-to-date cloud service. With Office 365, people can work together more easily from anywhere on virtually any device, while collaborating with others inside and outside their organization in a simple and secure way.

Office 365 works with the most popular browsers, smartphones and desktop applications people use today, including Mozilla's Firefox, Apple's Safari and Google's Chrome, and can be used on mobile devices such as Research in Motion's BlackBerry and Apple's iPad.

Office 365 for enterprises introduces an array of choices for midsize and large businesses as well as government organizations, starting for $2 or 1.75 euros per user, per month for basic e-mail. Office 365 for enterprises also includes the option to get Microsoft Office Professional Plus desktop software on a pay-as-you-go basis, for the first time ever. For $24 or 22.75 euros per user, per month, organizations can get Office Professional Plus along with e-mail, voicemail, enterprise social networking, instant messaging, Web portals, extranets, voiceconferencing and videoconferencing, webconferencing, 24x7 phone support, on-premises licenses, and more.

With Microsoft's online version of its Office suite of applications, the company looks to extend its customer base and beat back rival Google.

"We've been in the cloud for years supporting large enterprises such as Shell and DuPont, but Office 365 takes that same technology power and delivers it to small businesses," said Kirk Koenigsbauer, corporate vice president, Microsoft Office Division. "More than 70 percent of the people who signed up for the limited beta were small businesses, so it clearly strikes a chord."

For small businesses, Microsoft today also announced the Office 365: Ready for Work contest. To enter, qualifying businesses can share their stories on Microsoft's Office 365 Facebook page. Winners will be determined by community voting, and will be announced in September, Mirosoft said. The five winners will receive Office 365 for a year, as well as $50,000 in advertising and business services, and a Microsoft executive for a day - who will work at the winner's business or charity of choice.

Microsoft today also introduced the Office 365 Marketplace, providing a simple way for its customers to find apps and services when they want to extend and customize Office 365. The Marketplace is now live with over 100 apps and 400 professional services.