http://www.renpy.org/ I have been looking at this for a while; while I do not have the time/skills to make a game on my own, I really want to be able to make something with this engine. It is pretty damn easy to work with for basic projects. http://lemmasoft.renai.us/forums/index.php Forums with a shitton of documentation, guides and such for every aspect of the system, including ways of implementing an isometric RPG system. Incidentally, there's a competition held every March, under the name 'Nanoreno'. Those of you who like making games may be interested.