It just pries up one end of the hive, using a luggage scale and a pulley: the bees don't even move an inch as you use it.
This is still a decent amount of work. I would like to see a more automated system some day, that sits under the hive at all times and is powered by the PV cell and battery from a solaryard light. Ideally, the system would measure the hive's weight every five minutes or so. It could even be built to post updates to Twitter each day, with the weights and times that important events occurred on that day (maximum weight when all workers have returned, local weight minimum in the morning, time when maximum foraging is occurring...etc?).
"the qualities of these bacteria, like the heat of the sun, electricity, or the qualities of metals, are part of the storehouse of knowledge of all men. They are manifestations of the laws of nature, free to all men and reserved exclusively to none." SCOTUS, Funk Bros. Seed Co. v. Kale Inoculant Co.