“Smell is the most powerful trigger to the memory there is. A certain flower or a whiff of smoke can bring up experiences long forgotten. Books smell… musty and rich. The knowledge gained from a computer is… it has no texture, no context. It’s there and then it’s gone. If it’s to last, then the getting of knowledge should be tangible. It should be…smelly.”
Giles, Buffy the Vampire Slayer, S01 E08, I Robot, You Jane.