The digit at the end of the link can be 0-3, and you still end up at the `drunk mum' video. I don't know if this is interesting or not.

http://www.youtube.com/watch?v=ShpcjWG_Me0

http://www.youtube.com/watch?v=ShpcjWG_Me1

http://www.youtube.com/watch?v=ShpcjWG_Me2

http://www.youtube.com/watch?v=ShpcjWG_Me3

Edit: ...probably not, other video ids ending with a zero show the same behavior (see http://www.youtube.com/watch?v=AtKZKl7Bgu0)