Take a rape alarm (or other sonic device) and attach it to a helium balloon let it go a room with high ceilings and it will produce a noise disturbance until the battery runs out.
I cannot think of any ethical, life-affirming applications for this but I'm sure there is one.-- bob, Oct 14 2017 Self help: ?-- 2 fries shy of a happy meal, Oct 14 2017 A way of 'smashing plates' but not smash a plate? And like [2fries] said, feel better.-- wjt, Oct 14 2017 Alternative war methods? Bug thy neighbor until they move?-- RayfordSteele, Oct 14 2017 This makes me think of a new cat toy. A while ago MIT published a thing about focalized sound where you could narrow beam sound to any part of a room, so the sound was highly localized.
So you aim chirping bird sounds at different cat toys scattered around the room providing a followable circuit of amusement to the cat.-- beanangel, Oct 14 2017 Noriega Simulator 2017-- Cuit_au_Four, Oct 15 2017 random, halfbakery