Sonic Ether’s Unbelievable Shaders is a shaderpack that adds the kinds of effects we normally associate with ray-tracing— like light that’s able to bounce off other objects—to ol’ blocky-ass Minecraft, and do it while you’re playing in real-time.
It’s not technically ray-tracing (he’s actually using path-tracing), but the effects are still incredible. Here are some examples of it in action:
And here are some screens showing it off on some more traditional areas:
You can download what you need by pledging $10 over on Sonic Ether’s Patreon page. Just know that the effects here are software-based, so you’ll need a decent PC to get a good framerate.