Zope
Zope is an Open Source application server and portal toolkit used for building high-performance, dynamic Web sites. Zope consists of a number components which work together to provide a complete yet flexible application server package. Zope includes an internet server, a transactional object database, a search engine, a web page templating system, a through the web development and management tool, and comprehensive extension support. Zope's open support for web standards such as XML-RPC, DOM, and WebDAV allows you unparalleled flexibility and interoperability.