[laserdancepony]

Hardware accelerated 3D sound in video games a la EAX. That one went away with Windows NT IIRC and never surfaced again.

[JayStavis]

I think that the Apple Vision Pro might claim to have something _like_ this in audio raytracing?

[kridsdale3]

I think this was also a hyped feature of the PS5 when paired with specific Sony headphones.