Velcro
Swiss electrical engineer George de Mestral invented his first touch fastener when, in 1941, he went for a walk in the woods and wondered why Burdock seeds clung to his coat and dog. He discovered it could be turned into something useful. He patented it in 1955 and subsequently refined and developed its practical manufacture until its commercial introduction in the late 1950s.
Clothespin
Today, many clothes-pegs (also clothespins) are manufactured very cheaply by creating two interlocking plastic or wooden prongs, in between which is often wedged a small spring. This design was invented by David M. Smith of Springfield, Vermont, in 1853.
By a lever action, when the two prongs are pinched at the top of the peg, the prongs open up, and when released, the spring draws the two prongs shut, creating the action necessary for gripping.
Smith was also known for being an excellent violin player. It was one of his hobbies. He used to think clearly whenever playing violin, thinking about every day problems. That was how he came up with the idea to invent a clothespin.