Tetris — Javascript + HTML5
Here's a stand-alone library that plunks a Tetris game into some DOM, because nobody has ever written code for that before, ever.
The program's only requirements are jQuery and Underscore.js, which you probably already have loaded on your site. HTML5 is also a requirement; Tetris draws on a <canvas> element.
tetris.js exposes a single Tetris constructor function to the global environment:
Tetris($element), where $element is the jQuery object that the Tetris DOM gets injected into. That's it!
<script type="text/javascript" src="tetris.js"></script>
<script type="text/javascript">
$(document).ready(function() {
new Tetris($('div#tetris-game'));
});
</script>
The Tetris script .appends elements with id's "tetris", "tetris-canvas", "tetris-right", "score", "lines", "tetris-next-piece", and "start", so you probably shouldn't id any of your own elements with those names. I probably should've done a better job namespacing this thing, but never mind. There's also a CSS class "next-tetromino".