Sphinx is a full-text search engine, distributed under GPL version 2. Commercial license is also available for embedded use.
Generally, it's a standalone search engine, meant to provide fast, size-efficient and relevant fulltext search functions to other applications. Sphinx was specially designed to integrate well with SQL databases and scripting languages. Currently built-in data sources support fetching data either via direct connection to MySQL or PostgreSQL, or using XML pipe mechanism (a pipe to indexer in special XML-based format which Sphinx recognizes).
As for the name, Sphinx is an acronym which is officially decoded as SQL Phrase Index. Yes, I know about CMU's Sphinx project.
Platypus is a full-featured and easy-to-use page layout and typesetting system.
Inspired by technologies such as TeX, Platypus adds new features and, especially, ease of use to the generation of documents of all kinds. It is particularly adept at listing code, and so is frequently used for documentation. Input consists of text files with embedded formatting commands. These files are converted by Platypus to PDF, HTML, or Microsoft Rich Text Format (RTF).
Platypus is written in Java and relies on the iText library. It is available at no charge under the Apache open-source license. For more information, see the links to the left.
This site is tracking the progress of the XML Processing Model Working Group. It is maintained by Norman Walsh, chair of the WG, but is not otherwise affiliated with the WG or the W3C.