I call this one “oxymoronic”, which just about sums up a knitted snowman tea cosy in an Australian summer!
He is quick to make and takes less than 2 balls of “bobble” type yarn (eg “Ping pong” or “Marshmallow”) and 1 ball of 8 ply/DK, plus little bits for scarf and hat.

Update January 2017: I’m told that this type of bobble yarn is becoming hard to find in the US though it is still available elsewhere (search for bobble or pompom yarn).
If you are looking for an alternative King Cole Cuddles Chunky or 8ply will give a different but still fluffy “snowy” look.