If Apple could force you to buy a Mac to be able to charge your iPod they would. You can bet on that. And both nVidia and AMD already screw with you if you have an older card: There are hardly any bug fixes or optimizations for newer games for older cards, are there? I don't know where you live but clearly there is no competitive market around. Otherwise you'd know that by playing by the rules you won't be very successful. Sad but true. //edit: Havok is OpenCL based, so technically it is OPENly available and, as you already said, nobody uses it. It's a gimmick just like PhysX but nVidia at least use it. Of course it's a restriction and of course everything should be open for everyone but we'd hardly race ahead with that kind of speed in development if there wasn't that much pressure of competition.