Wikipedia
Xaira
Xaira is an XML Aware Indexing and Retrieval Architecture developed at Oxford University. It is based on SARA, an SGML-aware text-searching system originally developed for searching the British National Corpus. Xaira has been redeveloped as a generic XML system for constructing query-systems for any kind of XML data, in particular for use with TEI. The current Windows implementation is intended for non-specialist users. A more sophisticated and open-source version is currently under development. This version supports cross-platform working using standards such as XML-RPC and SOAP.