ChessDB is a free open-source chess database for Windows, Linux, Mac OSX and most UNIX and UNIX-like operating systems. ChessDB is based on code from Scid http://scid.sourceforge.net/ - a project for which there have been no updates for several years. In
ACDK - Artefaktur Component Development Kit - is a platform independent C++-framework similar to Java or C#/.NET for generating distributed and scriptable components and applications.
ChemVisio is software which might be useful for educational purposes (non-organic chemistry, crystallography etc.). It might be a good visualization support for all people who need better illustrations than that you could see in books.
PPR is a spooler for PostScript printers. It supports PPD files, and provides operator alerts, job result messages, and error recovery. It is integrated with Netatalk, CAP60, Samba, and Ghostscript. It has command line and web interfaces.
Das Projekt XNotar ist bzw. wird eine Datenbankverwaltung, basierend auf MySQL, Tcl/Tk sowie StarOffice bzw. OpenOffice, welche speziell für Notare in Deutschland zugeschnitten ist.
tmk - a tcl based intelligent ``make`` tool. This ``make`` tool combines the functionality of a traditional make utility with the power of the Tcl scripting language. tmk works on everywhere