C Scripting Language (CSL) is an embeddable scripting language with C syntax. A comprehensive set of libraries is included in the base package, and writing your own libraries is possible with an easy API for C programs, as well as a class interface for C++ programs. If you are looking for a compact and powerful scripting engine for your application, CSL might be the choice.
Flight Navigation Planner lets you make flight plans based on known airports, navaids, fixes, or cities. You can use the sectional charts, wacs, or the vector/terrain planning charts. It calculates headings, winds, time, and fuel. It features Airways-based Auto-Routing, Climb and Descent calculations (a/c type based), Fuel Stop Planning, Auto-Route around MOAS and Restricted Airspace, Hi-Res Weather Radar Overlay, Viewing of current sectional, wac, and IFR charts, the ability to see a route over TFRs, detailed nexrad radar overlays over your routes, Terrain Profiles with cloud ceilings, and the ability to upload flight plans to GPS.
PHP Mobile Mail is aimed at mobile professionals who want to use their favorite MUAs (noteably pine or mutt) on their laptop, either in UNIX or Windows (under GNU Gygwin). This lets you work offline. It includes a mail_spooler program, which accepts the output of you MUA and spools (on, or offline). When connected, another process parses through the spool and sends your messages. It is also designed to "fake" using your REAL email address with free services like gmx.net, or mail.yahoo.com, when using their POP and SMTP servers, assuming you have a domain and account that you can control to this degree.
QCad is a powerful but easy to use 2D CAD program for Linux, Windows, and Mac OS X. It uses DXF as its standard file format. While other CAD packages are often rather complicated to use, QCad tries to stay comfortable, and even an absolute beginner can create professional drawings with a minimum of effort.