TMugi started as an open project development of the Mugi model glider, but now has grown to include many aircraft, most of which are now powered. Mugi has a large Internet following and there are videos of Mugis from all corners of the world. The flight simulator is available for free download and the main program will remain free of charge. In contrast to a lot of games in this genre, it is being developed as an iterative prototype. This is an exciting approach as we don't quite know where it will lead, though we have a roadmap with many cool features.