Howdy Hamzter,
I was totally caught off guard watching that video. I was expecting cows, but not cows raining from the sky. Definitely made me crack up laughing. Great work and hope to see what else you decide to create in the future.
In case anyone else wanted to drop things into their level, Zak Parrish has a tutorial you can follow here: http://www.youtube.com/watch?v=9-7SmkasS_A&feature=youtu.be