Offers an Enterprise Wiki as hosted commercial service.

A Wiki Farm where basic Wikis are free. Offers plugins that allow applications and web sites to be built on a Wiki Framework.

Site offers free wikis for non-profits and communities. Run by a 501(c)3 non-profit itself, and contains numerous wikis using the Sycamore wiki engine.

Open source wiki application and farm in PHP with a MySQL backend that has MediaWiki-esque syntax with an AJAX interface.

A proprietary WYSIWYG personal wiki written in Python and JavaScript. Site contains a demo and signup information.

Site aims to combine the power of a database and the flexibility of spreadsheets with the collaboration potential of a wiki. Free version has a limit of 100 pages and 5MB of storage.

Hosted wiki farm offering WYSIWYG editing, folders, tags, PDF export, automated backups, and compatibility with MediaWiki (database standard, wiki-text) Source provided on purchase without rights for redistribution.

Private hosted wiki farm. Offers WYSIWYG editing, blogs, rss, full-text search, doc management, to-do lists, etc. Free version is limited to 10 users and 256MB with adverts.

MediaWiki hosting service with both free and premium, public and private hosting plans, with a dedicated staff team. Site contains a directory and documentation.

A wiki farm offering free hosting of Swiki (Squeak Wiki) based wikis.