cso is an easy to use C module that serializes objects into a simple binary format. It can be used to store data or to send it over a network. It supports either an object of type struct (CSO_DICT) or array (CSO_ARRAY) which contains elements of type integer of different sizes, double, binary, string, struct, or array.
libefgy is a set of C++ headers containing lots of templates loosely related to maths. The headers include templates for fractional arithmetic, big integers (and thus "big fractions"), calculating π, e, and some calculations with those (for trigonometrics), matrix manipulations, tuples, polar and Euclidian spaces in arbitrary dimensions, (perspective) projections, colour space manipulations in RGB and HSL, and assorted other things.
MorseCodr is a program for practising Morse code communication. You can connect to other users and send Morse signals that are automatically interpreted by the program. Once you become more proficient, you can reduce the amount of display and interpretation provided. It features Morse code tape display, dot/dash colouring, letter interpretation, and adjustable speed.