GraphicsMagick is a robust collection of tools and libraries which support reading, writing, and manipulating an image in over 90 major formats including popular formats like DPX, DICOM, BMP, GIF, JPEG, JPEG-2000, PDF, PNG, PNM, SVG, and TIFF. A high-quality 2D renderer is included, which provides a subset of SVG capabilities. C, C++, Perl, Tcl, and Ruby are supported. Originally based on ImageMagick, GraphicsMagick focuses on performance, minimizing bugs, and providing stable APIs and ABIs. It runs on all modern variants of Unix, Windows, and Mac OS X.
Xapian is a search engine library, scalable to collections containing hundreds of millions of documents. It's written in C++ with bindings for Perl, Python, PHP, Java, Tcl, C#, Ruby, and Lua. It is a highly adaptable toolkit that allows developers to easily add advanced indexing and search facilities to their own applications. It supports the Probabilistic Information Retrieval model and also a rich set of boolean query operators. Omega is a Web search application built upon the Xapian library. It can index a Web server's document tree (including HTML, PDF, OpenOffice, MS Word/Excel/Powerpoint/Works, WordPerfect, RTF, PS, etc.), or data exported from arbitrary sources (e.g. SQL databases).
MySQL Workbench is a cross-platform, graphical database modeling tool for MySQL. It allows you to create database models from scratch as well as by importing existing databases from SQL or DBDesigner4 models. You can then generate SQL code to CREATE databases, ALTER them, and export in various image formats and PDF/PS. Its extension system allows writing plugins and scripts in Lua, Python, and C++.
Bitfighter is a game that feels a little like Asteroids on steroids. It's a multiplayer space-based combat and strategy game, featuring customized ships, multiple game modes, cool retro graphics, and smooth network play. It also includes a full featured level editor, Lua scriptable bots, and other cool features. It has a very active development team, so the game keeps improving.
Renoise is a sophisticated music sequencer and audio processing application. It's an all-in-one music production environment for your personal computer. Based on MOD tracker software, its primary use is the composition of music using samples, (in WAV, AIFF, FLAC, Ogg, and MP3 format), plug-ins, and MIDI/OSC sequencing of VSTi/AudioUnits soft synths.
Naev is a 2D space trading and combat game, in a similar vein as Escape Velocity. Naev is played from a top-down perspective, featuring fast-paced combat, many ships, a large variety of equipment, and a large galaxy to explore. The game is highly open-ended, letting you proceed at your own pace.