Isn't the whole point of those battery-operated automatic fresheners to make things smell good? Normally, yes. But with a simple mod, it could be the world's best stink prank. Simply changing the liquid aromatic cleanliness of the freshener to something not so sterile and sweet is all you need to do.
Kipkay shows you exactly what to do for this sweet stink prank. First, get rid of the pressurized aromatic spray inside the freshener. Replace it with a small mouthwash sprayer. Empty the contents first and fill it back up with Liquid ASS! Mod the freshener a bit, and insert the bottle of Liquid ASS! It's now a stink-freshener.