Holy cow this is kinda spiffy and nicely done. Potentially significant...
Sometimes I’ll search .edu or .ac.* domains for tutorials, code, old physics and math graphics and Java applets. Often these sites are narrow in scope, but every once in a while, you come across a gem like this! I wonder if there’s a directory of high-quality college and university professor websites , though a web search for now does the trick (at least while it’s still public and not restricted to current students or faculty).