The opinion speaks for itself? (Interesting Judicial Comments)

"Ordinarily we count on gravity to keep heavy items in place; and so when flour barrels, armchairs, and truck wheels become airborne we assume first that something has gone wrong."

Circuit Judge Rovner, ruling on a res ipsa loquitur claim in Maroules v. Jumbo, Inc., 452 F.3d 639 (7th Cir., 2006).