AirTraffic is game that intends to put you into the hot-seat of an Air Traffic Controller. It is available freely to anyone under FSF's GPL license . The AirTraffic project consists of various server programs and a GTK/Gnome client at the moment. The client uses GTK/Gnome as it's UI and is being developed on and for GNU/Linux .
These are the current AirTraffic versions available: