>I remember a recent tool posted here (I think for OS X: maybe an editor) here by someone who was fed up with this extreme "input lag" and was guaranteeing his program would be answering in less than 16ms (maybe was it 24ms, don't remember exactly). But that is an exception.

Mac OS 9 Lives praise Mac OS 9 against OSX because of that.

http://macos9lives.com/