Btw, guys, let me begin by clarifying that I in no way represent id. I was a contractor there, and am no longer. (Actually, I'm at Human Head now working on Prey, so I've still got my nose very much in the tech ) As to id doing something like Make Something Unreal, I couldn't even guess. Hmm, an open source audio engine.. that's a tough one. I'm not a coder, so I can't really comment on what's possible or not. I guess theoretically ANYTHING is possible, but it would seem like a TON of work to me, because I'm guessing that you'd have to gut the original engine completely and code a new one. You're just opening a bag of hell at that point. Think about how tightly integrated the sound engine is with the world geometry, the portaling system, the animation system, func_movables.. I think you'd be better off adding to what's already there than reinventing the wheel. And though I don't know what audio special effects you all want/need from the audio engine, perhaps you should wait to see what future engine revs might bring, particularly from third-party hardware vendors. On lip synching.. gosh, well if you're a team lead and you're deciding what engine to use based on which game shipped with better lip synch anims.. ugh, you've got bigger problems.. Heh, never mind that you can run d3 at 800x600 with all the effects and shaders on and still be totally blown away visually, lip synch or no lip synch.