HolyGrail is an implementation of the GTD's next action list. In other words, it's a kind of todo list. It is composed of realms (contexts), quests (projects), and missions (todos). A realm groups missions, and generally represents a location or a situation, e.g. "at work", "at home", or "code". A mission is the next physical action to do to complete your goal. A quest is a succession of missions; it represents a goal. Every time what you are planning requires more than one next action, create a project.
Autojump is a tool that acts as a complement to cd: it makes navigating your filesystem a lot faster. It works by automagically maintaining a database of the directories you use the most from the command line, and allows you to jump back and forth between them, by typing just a few letters of the name of the directory you want to jump to. It works for Linux, Mac, and Cygwin under Windows.
PHP On Pie is a PHP framework that combines the best ideas from PHP projects like Drupal, CodeIgniter, Kohana, and ZendFramework. It has very few core concepts: classes, models, events, slots, and tools. It lets you repackage completed apps into plugins that you or others can use later. Its smart database classes allow you to implement vertical and horizontal partitioning (sharding) easily to handle millions of users.
Huxley is a set of classes that makes it trivial to produce legitimate output for queries made by the prevailing standard of REST queries. Instead of writing a network API with many methods, being run over RPC, you instead write only a couple of methods that are accessed by HTTP GET requests. You then return the results (in either XML, JSON, or text) for processing. XML and JSON are chosen because of the ease by which they can be parsed by most languages. In this way, you open up the scope of your network services to many more people than would otherwise have access to it.