The Saxon XSLT and XQuery processor, developed by Saxonica
eXist-db is a feature rich Open Source native XML database
Delphi : VRCalc++ OOSL & + (Paged List, TextEditor, VRAstroVision ...)
Delphi Java - VRCalc++ OOSL (Script) and + (Binary Exec Distro)
Evaluador de expresiones matemáticas para Java en español
A Java implementation of XProc: An XML Pipeline Language
Computer calculations made easy