GemRB is a portable open-source implementation of the Infinity Engine
Game engine to build text adventures.
Action RPG that's easy to mod
Open-source reimplementation of the original King's Bounty
GM tool for the RPG game "Legend of the Five Rings" 4th edition
The ECE is for creation and managing ED3+ED4 characters.
Real-time RPG for PC/tablet/phone; multiple quests and random dungeons
A complete web framework to create online Fighting Fantasy adventures
A suite of tools for any RPG system
Super Smash Flash 2 is the most must-play battle game with 28 classic
A fantasy RPG.
RPG character generator for RPG d20 systems.
[On hiatus] Zero-player role-playing game.
Harp Character Suite
Processes dialogue text files exported by the Bethesda Softworks SDK
IRB is a game creation toolkit
Alpha One is based on Vallheru
3D urban environment renderer : browser-app ; as well as a GTA clone
Random generators for tabletop RPG games (D&D, Pathfinder, D20, etc)
KCG is the (N)PC generation tool for the Kontinuum RPG system.