I was very disappointed not to see the source code for SkiFree here:

https://ski.ihoc.net/

But I still had to link it, because this game still brings back anxiety and that feeling of extreme nervous anticipation that haunts a child waiting to be eaten by an abominable snowman as he otherwise tries to ski down a damn slope! I was ~5--6yo back then. My son is turning 6 in less than a month. Fascinating perspective.