What is legal on airplanes?

The question nowadays is "What ISN'T allowed on airplanes?" Items such as aerosol cans; toothpaste; soda cans; and most (if not all) pressurized cans and aren't allowed on airplanes due to the fact people have miss used them as weapons. Then there's the obvious, guns; knives; sharp metal; any other type of weapon (blade.. etc.)