It's about 10,000 times as heavy as a Tennis Ball
In other words, 680 kilograms is 11,800 times the weight of a Tennis Ball, and the weight of a Tennis Ball is 0.00008470 times that amount.(ITF Standard; for Type 2 ball)
Per International Tennis Federation standard, regulation tennis balls must weigh about 0.0577 kilograms. Competition balls are also tested for bounce height, with the standards requiring that a ball dropped from 254 cm must bounce back to a height of 135 cm to 147 cm.
It's about 15,000 times as heavy as a Golf Ball
In other words, 680 kilograms is 14,810 times the weight of a Golf Ball, and the weight of a Golf Ball is 0.000067520 times that amount.(per R&A USGA Rules of Golf; maximum rule weight)
According to the Rules of Golf (as approved by the United States Golf Association and the Rules Committee of the Royal and Ancient Golf Club of Saint Andrews), golf balls must weigh no more than 0.04593 kilograms. Golf balls are not required to have the familiar dimpled pattern, but the design has been popular since its invention in 1905 because it reduces drag while increasing lift.
It's about one-fifteen-thousandth as heavy as The Eiffel Tower
It's about one-twenty-thousandth as heavy as The Brooklyn Bridge
In other words, 680 kilograms is 0.000051050 times the weight of The Brooklyn Bridge, and the weight of The Brooklyn Bridge is 19,590 times that amount.(a.k.a. New York and Brooklyn Bridge) (Manhattan and Brooklyn, New York City, New York) (total weight)
The total weight of the Brooklyn Bridge is approximately 13,320,000 kilograms. In a promotional event to prove the bridge's stability shortly after it opened, entertainer P. T. Barnum led a parade of 21 elephants across it in May of 1884.
It's about 20,000 times as heavy as a Light Bulb
In other words, the weight of a Light Bulb is 0.0000500 times 680 kilograms.(a.k.a. lamp) (for A19-size, 60w, incandescent bulb by Bulbrite; package weight)
A standard, sixty-watt light bulb weighs about 0.034 kilograms. The tightly-coiled filament inside a bulb of this size would measure about 579mm if uncoiled and stretched out.
It's about 30,000 times as heavy as a Battery (AA)
In other words, 680 kilograms is 28,000 times the weight of a Battery (AA), and the weight of a Battery (AA) is 0.0000360 times that amount.(Alkaline)
An "AA" size battery weighs 0.024 kilograms. AA batteries came into common use during World War II and were given their name by the American National Standards Institute (ANSI) Committee C18 because they were smaller than the "A" size batteries which were invented first.
It's about 30,000 times as heavy as a Mouse
In other words, 680 kilograms is 32,000 times the weight of a Mouse, and the weight of a Mouse is 0.0000310 times that amount.(a.k.a. "House mouse", Mus musculus) (adult)
The weight of a mouse is typically an average of 0.021 kilograms. While most mice typically live two to three years, the Methuselah Mouse Prize — an award administered by a non-profit organization which advances aging-related research — was once awarded to a team of scientists whose research resulted in a mouse living just under five years.