Atleto is an Open Source program for logging physical activites written in C++ using the Qt library. It is released under the GNU General Public License.
Kenozooid is software used to plan and analyse diving activities. Features like dive data plotting and analysis, dive computer support along with simple but powerful logbook maintenance and dive calculators are already implemented.
Knitter produces a 3-dimensional model of a knitting pattern. It supports KnitML, as well as a native language similar to that of traditional knitting patterns. It uses wxWidgets as a GUI framework and is available for Windows, Unix, and OS X.
Knitting Pattern Generator
Knitting Pattern Generator is a Python script to convert image files (PNG, GIF, BMP, etc.) into knitting patterns.
Knotter is a highly configurable Celtic knot designer.
KXStitch allows you to create cross stitch patterns on a grid using the supplied tools. It can convert images to cross stitch charts.
Model Railroad System
The Model Railroad System is a software package that can help you run your railroad. It allows you to operate your layout, from running trains to working your signals and switches. It has support for a network of Bruce Chubb CMR/I USIC, SUSIC, and/or SMINI nodes, and/or a network of Lenz's XPressNet DCC nodes. Software to create switch lists for freight car forwarding and create timetables for your railroad are included. There is software to help with photographing your trains, and to compute the correct value for those pesky dropping resistors for LEDs and/or incandescent lamps.
Nyagua is a little piece of software that may help you to manage your home aquarium. It can store data about measurements in aquariums and produce graphs from these.
TkWiCe is software for wine cellars. It is written in native Tcl/Tk, so it should run on any operating system with that interpreter (including any Unix like Mac OS X, Linux, *BSD, AIX, HP-UX, or Solaris, as well as PowerPC and Windows).