• Data mining algorithms for Collaborative Filtering (with some NNMF)
• Distributed computing and storage (including map-reduce technology such as Hadoop)
• Some minor work with CUDA early in it's history. However I now much prefer working directly with CUBLAS when I need large/dense matrix calculations. (So much so that I wrote my own Python/Numpy bindings for it.)
• Many NLP-related machine learning techniques including but not limited to information retrieval, stochastic language modeling, text generation, word sense disambiguation, entity recognition, etc.
• Some minor bioinformatics work.

• Wrote an automated multi-language classifier for an Arabic search engine company.
• Wrote a browser-based ontology editor (using Python/Django).

• Automated build and deployment processes (Ant)
• Version/source control management (CVS, GUI diff utils, etc.)
• Requirement/enhancement/defect tracking system (Bugzilla)
• Custom modifications to our tool-set provide automated code-to-requirement traceability (for example: CVS/Bugzilla Integration)
• Implemented an iterative, incremental development process which minimized both customer and company risk by providing a constant, visible stream of working features
• Implemented numerous automated development reports designed to provide complete USAF transparency into our development history, current progress and future goals
• Moved (carefully, slowly) our customer's interest away from a waterfall development mentality to many of the "agile" development principles

• Common, linked user interface used on all screens
• Database abstraction away from JDBC code in servlets and JSPs (similar to JDO, before it existed)
• Collection of reusable HTML generating software components, allowing rich GUIs to be developed quickly (many AJAX-like using hidden iframes and DOM manipulation, before AJAX was invented as an acronym and long before libraries of such tools existed)
• Common screen and data level ACL security implementation, with associated management tools
• Automatic database schema versioning, verification and upgrades
• All code reorganizations were done live, meaning they coexist(ed) with existing, working designs, as to afford the design change without incurring substantial delays and loss of functionality

Deseb - Django External Schema Evolution Branch
This is an implementation of schema evolution for Django. It is a stand-alone derivative of the original 2006 SoC implementation of schema evolution. Funded by the Google Summer of Code project.
http://code.google.com/p/deseb/

FlyBack - A "Time Machine" for Linux
A backup and recovery program modeled after Apple's Time Machine.
http://code.google.com/p/flyback/

DeSiGLE - Derek's Simple Gnome/GTK LaTeX Editor
A simple GTK-based LaTeX editor with spell checking, syntax highlighting, auto-completion and a PDF preview pane.
http://code.google.com/p/desigle/

gPapers
An open-sourced, Gnome based digital library manager (for managing research papers).
http://gpapers.org/

PyStatCVS
A Python reimplementation of the semi-abandoned StatCVS utility. (My major motivation for this was StatCVS's lack of branch analysis and extremely long run times.)
http://code.google.com/p/pystatcvs/

Distributed Issue Tracking System (DITS)
An issue tracking system that embeds itself into your distributed version control system so you no longer need to maintain a central Bugzilla/Redmine/Launchpad/GoogleIssues server. (very much a work in progress at this point)
http://code.google.com/p/dits/

NOTICE: These are all in varying states of maintenance and completion at any given time.