Air swimmers are radio-controlled balloons, the fins of which propel them. Wouldn’t it be fun to put a whole bunch of these in a giant “aquarium” and have a computer control their interactions?
Other fun uses of balloons (or bubbles) include the following ( Wikipedia):
- balloon helicopters (a full-scale one has been built!)
- bubble wrap (originally intended as wallpaper)
- light effects (e.g. glow sticks) carried by balloons
- balloon-powered water guns and rockets
- flogos, environmentally-friendly foam bubbles that retain the shapes of flowers, snowflakes, or logos:
Balloons have more serious uses, too. A rockoon is a rocket carried aloft with a balloon to save on fuel. An aerobot is a balloon used for planetary exploration ( Wikipedia).
Wikipedia’s article “fire balloon” describes a weapon that killed a pregnant American and 5 children out for a Sunday school picnic:
The Japanese fire balloon was the first ever weapon possessing intercontinental range, using the jet stream to take explosives from Japan to the United States during World War II. (One landed as far east as Michigan!) From late 1944 until early 1945, the Japanese launched over 9300 fire balloons, of which 300 were found or observed in the U.S. Fighters scrambled to intercept the balloons, but they had little success; the balloons flew very high and surprisingly fast, and fighters destroyed fewer than 20.
In what might have been an ironic twist of fate, one of the last fire balloons very nearly set off an uncontrollable nuclear reaction in the U.S. several months before Hiroshima. On March 10, 1945, one of the last paper balloons descended in the vicinity of the Manhattan Project’s production facility at the Hanford Site. This balloon caused a short circuit in the power lines supplying electricity for the nuclear reactor cooling pumps, but backup safety devices restored power almost immediately. As if explosives weren’t bad enough, the Japanese Imperial Army Noborito Institute cultivated anthrax, Pasteurella pestis, and 20 tons of the cowpox virus, the latter being enough, in theory, to cover the entire United States. Such biological weapons were never deployed, however.