Crows are pretty darn smart. In fact, all members of the Corvid family are renowed for their almost-humanlike brain work. I've written about the intelligence and quirky behavior of this bird family before here and here and here.
There's a new video hitting the internet that shows another example. It's from Russia and shows a crow (not sure which species, possibly a hooded crow) "snowboarding" on a roof covered in the white stuff using some kind of man-made disc. This behavior isn't going to help it find food, or a mate, or to hide from predators. Clearly, it's doing it just for fun.
Playing is a way to keep an active mind occupied or to practice skills that could help an animal in survival. It is considered a sign of advanced intelligence and we tend to think of it as a mammalian trait (apes, whales and dolphins, and social animals that need to think and strategize to hunt or avoid predators).
Ever see a lion cub pounce on a sibling and pin it down? That's an example of the latter purpose for play; pouncing on prey is a useful skill to have honed by the time the cub reaches adulthood.
What the crow is doing here seems to me to be an example of the former, play just for the fun of it. I can't say I blame it, it DOES look pretty fun!
Here's another video delving into the intelligence of crows.