This demo is my submission to the Mozilla Dev Derby of August 2011.
This is basically a Tetris integrated into the browser UI. The next piece shape is listed in the URL bar, your score is in the title bar and hover the page to display instructions (yeah, I know, this one in annoying...).
I've used the History API to display useful information about the game. Browser's back/next buttons are unused.
Enter a harder mode by pressing F11 ;-)

The code is available at https://github.com/gmarty/Mozilla-Dev-Derby-2011-08.

This demo is built using several open source projects:

Follow me on Twitter: @g_marty.