A Tetris game that uses the Impact.js game engine written in JavaScript.
Demo: http://www.ntaso.com/tetris/
Tutorial: http://www.ntaso.com/tutorial-tetris-with-impact-js/
Get the sources, download Impact.js (you need a license), unzip it. You have a folder in there called impact/lib/impact
that contains the engine's source code.
Copy it and place it in the Tetris source code under lib/
.
There's a text file showing the right location.
Have fun.