ROGUE WAVE!
This 2D simulator draws an ocean surface profile as the real-time sum of many independent wave trains sampled from a physically realistic wave spectrum. Raise the significant wave height to model a rougher sea, or add more wave components for a more finely textured interference pattern, and watch the live readouts as constructive interference between the trains occasionally focuses their energy into a single rogue wave — over twice the significant wave height — exactly the nonlinear-focusing mechanism believed responsible for real deep-ocean rogue waves like the 1995 Draupner wave.