@ajr i WISH i still had any of my hypercard stacks. no idea if they're still on some backup medium somewhere. i actually have some backup *tapes* kicking around (i forget the format!), but no tape reader to read them :(
@ajr they're not audio tapes, they're the specialized digital backup tapes, like the kind described in this old article (alas, the images are broken :( ) http://www.macworld.com/article/1014410/16reviewstape.html
@bunnyhero Oh, gotcha.
@bunnyhero No cassette deck?
If you know which computer they came from, interpreting those audio files is actually normally pretty easy. Some emulators can load them directly.