Timestretching involves changing playback speed while maintaining the originals pitch; it'd be handy if you only had, say, 15 minutes to listen to 20 minutes of audio (or just didn't fancy wasting 20 minutes on.. whatever you're listening to, maybe even an audiobook or so). It's also a nifty feature even if you don't have a use for it

So, um, if anyone's on the lookout for a project... <grin>