Free to extend software for linux

GetMeDone is a task manager in the spirit of Getting Things Done. It uses PostgreSQL as a backend and is written in Tcl/Tk.
Currently only tested on Linux, it should be easy to extend to run on Mac OS and Windows.
It features easy filtering of contexts, priorities, and time, advanced recurrent tasks, linking tasks to projects, deadlines, an ideas list, and the ability to defer tasks to future dates.
Enhancements:
- Fix bug with editing task with today as the deadline

LUA is a small scripting language designed to be embedded inside your application to provide extensibility.
It is also possible to extend the Lua scripting language itself via the use of extensions written in C. This page describes such an extension which provides a small number of basic networking and filesystem primitives.
By installing this extension you will be able to write networking applications in the Lua!
Enhancements:
- Added some filesystem primitives.
- Added API documentation & examples.
- The HTTP server now falls back to a default virtual host if none is specified, or if the attempted one doesnt exist.
- The HTTPD server now supports directory indexing if no index.html file is found in a directory.
- The HTTPD server now writes access.log files to each virtualhost.

The Java Exorcist projects aim is to create a small and easy to use tool, that can be used to extend the Java language syntactically. Why would you do that? There are basically two reasons:
First, you just might want to fix your pet-peeve in the language itself. For example, create new keywords like unless, foreach, new operators, or generate setter getters automatically for a bean property.

Secondly, you might tune the language itself for a specific project, so the project code may look more clean and thought out. For example: specific logger keyword, which automatically checks (if statement) whether the logger should be invoked or not, or even ommits the whole logging compile-time, when its disabled! Or create a method modifier transaction to enclose the whole method in a project specific transaction.

How it works on the outside

Exorcist is a compiler of extended Java code. The compiler can be used in command-line mode, or through Ant. Basically, with no extensions configured, Exorcist only compiles the standard java code. To extend the language, you can plug in classes, which extend a single interface of the exorcist framework, and implement a single (and simple) method. Thats it.

How it works inside

Exorcist works like a pre-processor. It translates the extended language into plain Java code, and then compiles it using the standard Java compiler (javac).

To analyze a language, there are two steps involved. The first is a Lexical analysis, the second is the Parsing of the lexical tokens. Lexical tokens are strings, numbers, operators, dots, semicolons, etc. These are also called terminal symbols, because they can not be analyzed further. During parsing, lexical tokens are read, and non-terminal symbols may be produced.

These include things like: expression, method body, declaration, if-statement, etc. The Exorcists tranformation engine works basically with lexical token lists. Each extension first matches itself to the start of the received token list, using terminal and non-terminal symbols freely. If the match is detected, the extension is free to modify the input token list as it pleases, and with it modify the output clean Java source code.

QtHello project is an Othello game and toolkit.

Its design makes it easy to extend both the computer player and human player interfaces. It currently has 6 different computer players ranging from completely random to tree search with Alpha-Beta pruning.

Its mainly meant as a toolkit for Othello developers wanting to concentrate on the AI routine and not the GUI. Although I think normal Othello entusiasts might find this game enjoyable especially when the computer players get smarter.

Technika was developed for the computer security professionals to automate common exploitative task from the browser. It acts like a standard OS shell scripting environment. You can script everything from the currently viewed page just like Greasemonkey. You can autorun bookmarklets and perform safe operations on the currently viewed resource.

If you have ever needed an easy, powerful and safe way to extend web resources that you visit in a cross-browser manner, Technika is probably the right solution for you. It integrates with Firebug and provides a great environment for developing bookmarklets.

Project Lancelot is a modular mailing list manager.
Far simpler and less feature-rich than the likes of Mailman, it is still quite easy to understand, to change, and to extend.
Project Lancelot is a work in progress and should not (yet) be used for serious applications.
Enhancements:
- This release adds automated bounce processing via VERP.

Marathon project is a testing framework for GUI applications developed using Java/Swing. Marathon composes of recorder, runner and editor. The testscripts are composed of python code.

Marathon focuses on end-user testing. One need not know Java or Swing to record test scripts using Marathon. Marthon is kept intentionally simple. The aim to produce test scripts that are readable by everyone on the project. This includes the developers, testers and the customers. Marathon is flexible and provides facilities to extend the functionality available through python scripts or through writing ones own component resolvers.

Marathon captures the semantic actions on components instead of the mouse & keyboard events. This results in scripts that are simple and at a higher granular level. Marathon suites well for applications that mostly depend on forms-paradigm.