This one I shot about 25 days ago with a friend's Nikon Coolpix. For obvious reasons, one of those things that can't go unnoticed (5 years and 1369 days ago)
This machine equipped with a membrane on one side and a small hole on the other can, by hitting the membrane, create air movement (wind) that comes compressed through the hole.
Very impressive ! (5 years and 1915 days ago)