whym.org
WikiHadoop
a module to let Hadoop digest terabytes of MediaWiki dumps with full page history
RevDiffSearch
a Lucene-based full-text search and visualization system for MediaWiki revisions
growthring
fast suffix-array algorithms to identify repeats
TinyClassifier
a machine learning library powered by SWIG
Commons App
an Android app for sharing free photos
Pywikibot
an automation framework for MediaWiki websites
good-faith-collaboration-ja
ウィキペディアについての本 Good Faith Collaboration (Reagle, 2010) 、日本語訳
For more, see my repositories and papers.