pbForth

Programmable Brick Forth (Ralph Hempel) — a replacement firmware that turns the RCX into an interactive Forth system. You talk to a live Forth interpreter on the brick over the IR tower as a serial terminal, so words can be typed and tested interactively instead of compile-and-download.

• Alternative LEGO-firmware replacement, like legOS · brickOS (C) and leJOS (Java).
• Good for live experimentation and teaching Forth on real hardware.