I have M3D noted as Quake 3 model format. If you have 3D Exploration that will read and convert the model into other formats. I seem to recall seeing somewhere on one of the Japanese sites a link to a program that some of them use (written by a friend/associate???) that creates these things. It seems to be very popular over there anyway. The M3D models can be converted but I don't know of anything except 3D Exploration that can do it, unless MilkShape will - that seems to handle Half Life and other models well enough.