Well i tried to emulate an amiga under mac osx using MAXuae and i even tried to run it under linux {YDL), unfortunately both suxx. The linux version is a big let down as nvidia dont write ppc graphics drivers so you loose loads of performance from that. an the native osx version is still very beta. Maybe mac and amiga users only ever cross over very rarely so this is why there isn't as much people working on a mac version
