Gliffy is a web application that allows you to create diagrams and layouts online, share them with your coworkers and publish them on the web. Gliffy was developed in Flash and is more responsive than Ajax applications like Google Spreadsheets. So what can you create with Gliffy?* Flow charts
* Workflow documents
* Class Diagrams
* Network Diagrams (like in this diagram)
* Database schemas
* Website layouts/wireframes
* Room plans
You can export the diagrams in SVG, JPEG and PNG formats, so it's easy to publish them on a web page or to import them in a more powerful tool like Microsoft Visio. Gliffy keeps track of all the revisions of a diagram, so it's easy to revert to earlier versions.
You won't find too many templates like in Microsoft Visio, you can't incorporate too much data in the diagrams, there aren't UML diagrams, but Gliffy is a useful tool for those who don't need all these features. Besides, unlike Microsoft Visio, Gliffy is free and seems a perfect fit for Google Office package.