Hyperbolic space with webVR support. WASD + Arrows to move, space or p to play/pause. Numbers 1-9 give different models.
A websperience by Vi Hart, Andrea Hawksley, and Henry Segerman, using the hyperbolic space prototype developed at a hyperbolic webVR "hackalot" with Vi Hart, Mike Stay, Henry Segerman, Andrea Hawksley, and Andrew Lutomirski, with help from Marc ten Bosch's 4d graphics shader, Jeff Week's Curved Spaces, Mozilla's webVR framework for THREEjs, etc.
Try it at: https://hawksley.github.io/hypVR/