I made this video a while back: The black box is a bitcoin miner (irrelevant) with a fan that blows upwards just underneath the holes. I was trying to make the piece of paper float. I think this should be possible since the air velocity is higher on the outsides of the fan than in the center. I seem to recall air "guns" that could float a light-weight ball in the air. Is that actually possible or am I overlooking something?