GemRB is a portable open-source implementation of the Infinity Engine
GemRB (Game engine made with pre-Rendered Background) is a portable open-source implementation of Bioware's Infinity Engine.
It was written to support pseudo-3D role playing games based on the Dungeons & Dragons ruleset (Baldur's Gate and Icewind Dale series, Planescape: Torment). It should run on GNU/Linux, Microsoft Windows, OS X, possibly other UNIX derivatives and more. It is licensed under the GPL.
The OHRRPGCE (Official Hamster Republic Role Playing Game Construction Engine) is a game maker that you can use to create your own RPG game in a style similar to the classic Final Fantasy games on the NES, SNES and GBA which have so shaped the RPG genre.