I found this site called elfyourself.com. It is hilarious and the ultimate example of interactivity on the web. On this site the user literally becomes a part of the animation. It is sponsored by Office Max to bring holiday cheer to all of its customers, and gain a few more in the process. I posted earlier about how interactive sites boost sales!
The website works by uploading a photo of yourself. The website allows you to adjust the size and cropping to get the perfect picture of your face! Next you will adjust your mouth, so your animation can sing, of course! After this is done you can add friends. You can have up to 5 elves within your animation.
Finish adjusting your friends and play your animation. If that doesn't put you in the holiday spirit, I don't know what will!