When I'm livestreaming on Twitch, this page will show my stream and a chat overlay. Simple enough right?
Click the screen to begin, and you'll play one of these DOS games, selected randomly: Jill of the Jungle, Duke Nukem 1, Commander Keen 4, or Doom (all free Shareware!). To play something different, just refresh the page! Normal keyboard controls should work. (Mac users may want to disable Mission Control shortcuts.) If you do something stupid at the DOS prompt that stops the game working, just use the factory reset link at the bottom. Save games will persist across sessions, factory reset notwithstanding.
Tap on the screen to launch a random non-interactive "Cracktro". A "Cracktro" is a little audiovisual demonstration written by the people that wrote cracks for pirated games in the 80s and 90s. They left these "cracktros" with the game as a kind of calling-card.