A few others if you like: For an average man (5'10") or woman (5'4"), one meter is very near the distance of your navel above the ground while standing barefoot (women are shorter than men, but have longer legs, so the navel is surprisingly stable). 150 centimeters is 5', or the distance from the ground to your mouth if male, to your eyes if female. An average man is 180 cm tall, and weighs the same, in pounds. An average woman weighs 125 lbs, so average humans, in groups, weigh close to 150 lbs. each. A heavily dressed man--with overcoat and gumboots, weighs 200 lbs. Ditto a normally dressed man, soaking wet. (in the US, add 10% to these numbers. Sorry)

One cubit = 500 millimeters. Thus 300 cubits = 150 meters. Big boat. 30 meters = 100 ft. 30 centimeters = one foot (1.5% error).

An American bill, whether one dollar or 100 dollars, weighs precisely 1 gram. As they wear they become dirty, maintaining almost precisely their initial weight (dope dealers count large amounts of cash by weighing it). A nickel weighs 5 grams. One dollar's worth of nickels weigh 100g, roughly one-quarer pound.

A pint of water weighs a pound ("A pint's a pound the world around") 4% error.

An average man, at a brisk marching pace, will have a stride very close to 32 inches (the Roman mile is derived from this = 1000 double paces = 5280 ft). A bit more relaxed pace and most can figure 30" exactly.

An American football field, minus the end zones, is near an acre. Two American football fields side-by-side, now *including* the end zones = one hectare.

All the above are slightly inaccurate, but are easy to measure, remember and intuit.