GPUs are good at large bundles of related tasks, saving die area by tying several chunks of data together. This is commonly used for graphics, where screens have two-to-eight million (1080p to 4K) pixels, 3d models have thousands to millions of vertexes, and so forth. Each instruction is probably done hundreds, thousands, or millions of times, and so parallelism greatly helps with utilizing real-world matter to store and translate this data.
Audio is another area with a lot of parallelism. A second of audio has tens of thousands of sound pressure samples, but another huge advantage is that higher frequency sounds model pretty decently as rays, which can be traced. NVIDIA decided to repurpose their OptiX technology into calculating these rays. Beyond the architecture demo that you often see in global illumination demos, they also integrated it into an Unreal Tournament test map.
And now it’s been released, both as a standalone SDK and as an Unreal Engine 4.15 plug-in. I don’t know what its license specifically entails, because the source code requires logging into NVIDIA’s developer portal, but it looks like the plug-ins will be available to all users of supported engines.