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Though they began as simple toys for kids, rubber ducks have had many surprising additional uses throughout history! Rubber duck races are a common way for charities to raise money. Organizations will allow people to buy rubber ducks which are essentially raffle tickets. They then dump thousands of these rubber ducks into a course on a river or pond and the owner of the first one to cross the finish line wins a prize. They usually look a lot like this. Rubber duck debugging is where you explain a problem to a rubber duck as if it were a real person in the hopes of solving the problem by talking it out. Rubber ducks were once used in an experiment to test the pollution caused by different kinds of jet ski engines (photo). Those particular ducks are now mounted on the desk of politician Mark DeSaulnier, D-Calif. There have been many famous art projects involving rubber ducks. The most notable one is the giant rubber duck by Florentijn Hofman which has been shown all over the world. Using the popularity of the giant rubber duck, Chinese activists used rubber ducks to protest censorship in China. They replaced the tanks in banned photographs of the Tiananmen Square massacre with giant rubber ducks as a way to avoid censorship. As a result, searching for rubber ducks is now also banned around the anniversary of the massacre (source) Protestors in Brazil also have a use for giant rubber ducks! One common slogan to protest tax increases is "Não vou pagar o pato" which translates to "I will not pay for the duck", so giant rubber ducks can commonly be seen in demonstrations. Example with more info here There are several cases of people floating rubber ducks in large puddles from potholes as a way to protest bad road conditions (example) Because they're so collectible, rubber ducks make great promotional items. Many hotels will include custom rubber ducks in their bathrooms. American manufacturer Celebriducks has a long list of all the promotional rubber ducks they've designed over the years here Rubber ducks have been used for sound effects in surprising places. The song "Drain You" by Nirvana features one as well (source). The same duck is also featured of the back cover of their album, Incesticide. A rubber duck once saved a 90-year-old woman's life. She fell in her bathtub and was trapped there without help for 3 days, surviving only by storing and drinking water from her rubber duck (source) If you want to learn more cool things about rubber ducks, check out /r/rubberducks! I try to make sure the subreddit is updated daily with new sightings and facts!