ScrewTurn

ScrewTurn Wiki is a performant and simple Wiki engine, written in C# and based on the ASP.NET 2.0 platform.  ScrewTurn Wiki is a fast, powerful and simple ASP.NET wiki engine, installs in a matter of minutes and it's available in different packages, fitting every need. It's even free and opensource.
Its main features are described below.
- Free and open-source
- No need for a database (but SQL Server and MySQL are supported with Plugins)
- No need to touch IIS or ASP.NET configuration (works in ASP.NET Medium Trust environment)
- High performance and scalability on every hardware configuration, thanks to a smart and configurable content caching system
- Low bandwidth usage, thanks to the (configurable) usage of custom ViewState Compression and HTTP Compression
- Simple deployment, administration and usage
- Small footprint
- Theming available entirely through CSS files (CSS Media Types are fully supported)
- Automatic page backups (performing a rollback is as easy as a mouse click)
- Simple user accounting system (with Administrators and Users and a built-in admin account)
- Useful features such as Page-level coarse-grained authorization, the possibility to make the Wiki completely public (no registration needed to edit pages) or Private (anonymous access is not allowed)
- Page Categorization and Discussion
- Page Transclusion and Snippets
- Plugins support (see documentation)
- Protection against dangerous files, scripts and spammers (Captcha control on registration)
- Multilanguage interface (English, Italian, French, Spanish, German, Brazilian Portuguese and Russian)
- RSS 2.0 notifications for every page as well as for the whole Wiki and for Page Discussions

Go to http://www.screwturn.eu/

See also these related projects.