At the Professional Developers Conference on Tuesday, Microsoft has announced that Office apps Word, Excel, and PowerPoint are going online. This will not affect the traditional versions.
Browser-based Word, Excel, and PowerPoint offered via Microsoft's Office Live Web site, while businesses will be able to offer browser-based Office capabilities through Microsoft's SharePoint Server product.
The company has not revealed its entire pricing strategy, although representatives note that the current Office Live has both free, ad-supported options as well as subscription services.
You can access the service from its offical page at http://workspace.office.live.com using your Windows Live account.