A video was posted on here not too long ago with Surly's art director Andy Wood. It was quirky and weird, well, mostly weird. In that video he talked about Surly bikes for taller riders.
This video brings us to their fatbikes. Supposedly they are trying to show how much fun you can have on a fatebike while goofing off, that's my guess anyway. One of the Surly guys rides around a field on a fatbike with a unicorn on his head. Strange stuff..