a powerful, inexpensive version control system for Windows. Based on the widely used GNU RCS, it is fully integrated with the Windows Explorer, providing the most intuitive and easy-to-use configuration management and change control solution in the market
a document-driven quasi-wiki product - upload just about any kind of file (office docs, images, whatever) and Versionate will create an editable, wiki-like page with version and access controls
a popular version control system designed to handle very large projects with speed and efficiency; it is used mainly for various open source projects, most notably the Linux kernel.