I am a dedicated user of and advocate for free (libre) software. I regularly contribute bug fixes and new features to packages that I use, and listed here are a few software bundles of my own. See also: github.com/league/
LZMA Streams in Java — LZMA is the compression technique used in the 7-Zip archiver. This provides a thin layer over the LZMA Java SDK to support transparent compression of Java input/output streams.
RNGzip — type-based XML compression. The code from my research paper in DCC07. It uses the Relax NG schema to substantially compress conforming XML documents.
MetaOCaml Server Pages — web publishing as staged computation. The code from my research paper of the same name.
QCheck/SML — automatic unit testing for Standard ML, modeled after QuickCheck for Haskell (by Claessen and Hughes).
AI Lab Workbook in Scheme — these are the projects from my JCSC paper in May 2008.
TeX support for the FontSite 500 CD — no longer supported.
Scotland Yard, an historical look at an undergraduate programming project.