Wiki-OS simulates an operating system inside your web browser. It lets you to launch rich-client applications without installation and access your data from any computer connected to the Internet. Applications are executed in a sandbox that securely isolates them from the rest, so that your computer is always protected.
Similarly to how you can put a YouTube video on a website or blog, you can put a Wiki-OS application inside any web page. Just click the "embed" button at the top-right corner of any application and copy/paste the code snippet.
Wiki-OS includes all the tools to get started writing Silverlight and .NET applications in seconds. It provides a built-in source control to work collaboratively. The code editor supports C# 4.0 and provides syntax highlighting, auto-completion, and an easy-to-use User Interface designer.
Just append the name of a project and a class to the Wiki-OS.org address and you have a direct link (e.g. www.wiki-os.org/CalculatorProject/Calculator to launch the calculator).
Wiki-OS includes patent-pending technologies by Userware to make contributing to an application as easy as modifying an article of a wiki.
(the screenshots in the diagram above are taken from the WPF-based version of Wiki-OS.org)