Berglet / emulator
A Berglet in your browser.
Not a video and not a remake: this is the console's real system, running on a copy of its chip made of JavaScript. The window is the console. Games come from the Market: every game's page there has one to play, and a button that brings it here, bigger, at the moment you left it.
To put one on your own page: <script src="https://berglet.com/emu/berglet.js" data-game="GAME"></script>