There is a new easter egg on youtube where you can play snake in the actual video itself, it can be any video as long as it is the new player(with the transparent play bar).
To Play snake on a youtube video.
1. Pause the video.
2. Hold down the left arrow key on your keyboard for a second or two.
3. Enjoy.
You can't play in embedded videos.
Here is a video with a blank screen so you can play without distraction.
http://www.youtube.com/watch?v=0RzTXFF0OYE