Toni Uusitalo has posted Parsifal 0.8.0, a minimal, non-validating XML parser written in ANSI C. The API is based on SAX2. Version 0.80 adds support for processing the DTD, something that's necessary even in a non-validating parser to supply default attribute values, identify ignorable white space, resolve entities, and so forth. Parsifal is in the public domain.
Eric S. Raymond has released version 1.9 of doclifter, an open source tool that transcodes {n,t,g}roff documentation to DocBook. He claims the "result is usable without further hand-hacking about 95% of the time." This release supports the Vt macro in mdoc. Doclifter is written in Python, and requires Python 2.2a1. doclifter is published under the GPL.