Just to get it out of the way: This is fake.

A couple years ago, somebody took this video, animated the tail and added the noise - but that doesn't make is any less awesome. Having a bad day? Save this video, and play it back to make yourself smile. I've already watched it a dozen times, and I giggle every time.

It also answers the age old question: "If A Deer Farts In The Woods, Does Anyone Hear It?"