EduMIPS64 (aka edumips) is a cross-platform MIPS 64 ISA simulator. It can be used to run and debug MIPS programs that are written using the MIPS64 instruction set. It supports visual debugging and lets you see what instructions do in the pipeline.
Accha is a cross-platform (Java/Swing) application to help students learn languages. AcchaNi is intended for Japanese (kanji) study, and the original Accha is intended for the Hindi (Devanagari) script.
Molle is a cross-platform prover for modal logic, which exploits the modal semantic tableaux method. It features a very usable graphical interface, with interactive representation of generated models. Molle is maintained by Politecnico di Milano.
Applications that use and display SignWriting symbols. Applications are based on a library of common operations instead of recreating the same logic for each app. The library is built on the portable wxWindows cross-platform application framework.