ZapNote: Ipedo
Ipedo has developed a proprietary, hierarchical, in-memory database engine aimed at storing XML documents "natively". The Ipedo XML Database uses memory techniques to get substantial performance gains versus some other NXD approaches. Built as an all-Java server, the Ipedo system is meant to be easily integrated with typical application server environments. Ipedo has extended XPath for search across multiple XML documents and has also included XSLT transformations within the data store itself.