That's one of the main goals of Hacker League. Maybe we can't keep the actual hacks online, but at least we can preserve a list of what got made and who made it.
And we don't really know what they had to do to make it work. The <audio> api is not known for its robustness and accuracy.
Our hack from October was really simple (two small python modules), but we spent all day compiling midi libraries to use with python. That was definitely not easy work.
In this case, Cloudspeaker.