XTF

Available

 * Web site: http://xtf.cdlib.org/
 * Code repository: http://sourceforge.net/apps/trac/xtf/wiki

Lead developer

 * Martin Haye

Description
From the repository (accessed 2010-06-07):

"The eXtensible Text Framework (XTF) is a flexible indexing, display and query tool that supports searching across collections of heterogeneous data and presents results in a highly configurable manner. XTF is an open-source project of the eScholarship Publishing Group of the California Digital Library, and is deployed in academic settings worldwide."

XTF is a customizable search engine powered by Lucene, which uses XML and XSL transforms for the search and display of documents.