Source: http://lifehacker.com/5557862/office-web-apps-open-for-use
Office Web Apps, the free, cloud-based viewing and editing suite that Microsoft promised would be available to everyone, has opened wide its doors. It's a decent set of basic-plus editing tools, powered by SkyDrive's generous 25 GB of storage space.
As you can see in the screenshot above, Microsoft's free editing tools, like Word, aren't anything close to a replacement for its desktop suite, but it is an experience fairly comparable to Google Docs. They've even added in real time collaborative editing, and, presumably, there's greater formatting compatibility with Office documents you upload.
Head to office.live.com in your browser—any browser, it seems—and you'll get a list of the documents you've uploaded to SkyDrive, with Bing-powered search and some basic filtering. Head there in a smartphone, and Microsoft promises you'll be able to at least view your documents in most smartphone browsers. If you're a Live Messenger users, there's additional functionality in store for you, and Hotmail die-hards should get some extra neat features soon.
Office Web Apps are a free set of tools to use, and require a Live account. If you're not in the U.S., UK, Canada, or Ireland, you can access a no-country-restricted version of the Web Apps here, though not in any language but English at the moment.