Topologic is a simple renderer for certain higher-dimensional geometric primitives and some regular 3D shapes. The idea is to make it easy for students of certain higher-dimensional maths and physics topics to visualize the typical primitives in those fields and get a grasp for the topic. Note: the program as such is freeware, while the part of it that deals with the Mathematics to project the geometric shapes to 3-space and 2-space has been released separately under an MIT/X style license.
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.