joyd is a very flexible program that allows you to execute commands via a joystick or joypad attached to your computer. One simple possibility would be to reboot when your keyboard is hung. It can use any device supported by the Linux Joystick Driver. Helper applications allow you to test the joystick status in your own shell scripts.
JERED is a very easy-to-use C/C++ text editor for *NIX which provides C/C++ syntax color highlighting. Help is always on the screen, many-user configurable settings are available, and the user interface can be viewed in English, French, Finnish, Spanish or Russian (using the KOI-8 font).
The JACAL Project is a suite of programs, scripts, guidelines, protocols, documentation, and diskettes that assist in quick, network based loads/builds of machines. It has been used to build 70 University lab machines from scratch (No OS) in two hours. This includes NT service packs and 80+ applications on the NT side.