Web-based office applications have reached top heights these days: bringing together several features you won’t find in traditional office software i.e. Microsoft Office. These include: document sharing, group collaboration, support for all popular Office file formats, and remote access and editing. Although it’s still yet to reach a stage where it can be used as a viable alternative to your local office software, it definitely makes an excellent complimentary tool. So in case you’re looking for a free, all-in-one type web-based office suite than one of the below ones should be a good place to start with.
(1) Zoho – Office
Very well implemented, all-in-one type office suite. Zoho consists of several stand-alone applications ranging from must-haves i.e. Zoho Writer (for Word processing) , Zoho Sheet (for Spreadsheets) and Zoho Show (for Presentations) to more specific tools i.e. Zoho Project and Zoho Meeting. Additionally, Zoho provides a handy plugin for Microsoft Office letting you work on office files offline and quickly sync them afterwards.
Thinkfree provides solid and well-integrated office suite, supporting 3 main office applications: Word, Spreadsheets (i.e. EXCEL) and Presentation documents. Once you sign-up, you’ll be provided with an easy-to-use control panel (aka Webtop) where you can create, edit, store, organize and collaborate on documents. ThinkFree also features a premium version (non-free) which lets you work on your ThinkFree docs both online and offline. More on ThinkFree
(3) Google Docs & Spreadsheets
Unlike Zoho and ThinkFree, Google Docs doesn’t provide support for working with presentation files (i.e. Powerpoint). However, it really does an excellent job, when it comes to Word and Spreadsheet docs . It is clean, simple to use, feature-rich, collaboration friendly and fast. Read more on Google Docs here OR check out Demo (with Screenshots).