There are some inventions and inventors you just grow up knowing about - Alexander Graham Bell and the telephone, Thomas Edison and the lightbulb (even though he really just improved upon it). But there are a lot of inventions lurking out there that you didn't learn about in your elementary school history and science books - inventions from geniuses known for other creations and discoveries, and inventions from people you didn't expect to be inventors at all. Here are a few of them.

Henry David Thoreau, of all people, invented raisin bread when he tossed a handful into the dough he was baking while at Walden Pond. It doesn’t sound like a big deal, but the addition of the shriveled little grapes is said to have just stunned and scandalized the housewives of Concord, Massachusetts, who were used to doing their baking in a very particular manner. I bet their minds would be blown by cinnamon raisin bread. Photo from Food Channel.

Marlon Brando: actor, icon... inventor? Yup. Toward the end of his life, Brando received several patents all related to a device that would help musicians tune drumheads. Why? Your guess is as good as mine - the patents all stemmed from 2002-2004, and when he died in 2004, he presumably took the idea with him.

Zeppo Marx owned a company that made industrial clamps and straps that were used quite heavily during WWII - the Marman Clamp was actually used to hold the atomic bombs carried by the Enola Gay. But Marx himself held three patents - one for a “Vapor Delivery Pad for Delivering Moist Heat” and two related to a device that monitored heart rates. And actually, Gummo Marx had a patent too - it was for a “Packaging Rack.”

Sir Isaac Newton was undoubtedly a genius with many discoveries and inventions to his name. Where do you think the cat flap ranks on his list of accomplishments? Rumor has it that Newton invented the cat flap when his beloved pet kept nudging the door to his lab open while he was working on light experiments, ruining hours of work. But he loved his cat and didn’t want to shut her out of his lab - or trap her inside. The solution? He cut a hole in the door, then installed a piece of felt at the stop so the least amount of light possible would seep through. Allegedly, when the cat had kittens, he cut a smaller door for them to go through even though they easily could have gone through the larger door. However, take this story with a grain of salt - at least two Newton biographers have done extensive research on the man’s life that turned up no trace of a pet of any kind. Photo from DIY Happy.

What’s a parent to do when their helpless infant is suffering after a terrible accident? Well, if you’re Roald Dahl, you team up with a couple of other guys to invent a brain shunt to ease the pain. Dahl’s son Theo was happily sitting in his baby carriage when it was hit by a taxi cab, severely injuring the infant and causing water to pool on his brain. The current device that helped drain the fluid was unreliable; it often jammed and was known to cause blindness. So Dahl partnered with a hydraulic engineer and a neurosurgeon to come up with a better solution - the Wade-Dahl-Till valve. His son had recovered by the time the valve was complete, but it served others well. The three men responsible for the valve all agreed that they would never accept payment for the invention.

Mark Twain has three patents to his name, but he was mostly a wannabe inventor. He was fascinated by inventions and gadgets and invested a lot of money in unknown inventors in hopes that his investments would make him quite rich. None of them ever panned out, though, and he eventually declared bankruptcy. But back to Twain’s patents - they were quite diverse. The first was granted in 1871 and was called “Improvement in adjustable and detachable straps for garments.” The strap tightened shirts up at the waist; the idea was to replace cumbersome suspenders. He also held a somewhat successful patent for a self-pasting scrapbook that ended up earning him about $50,000. And in 1885, he filed a patent for a history trivia game. It should come as no surprise that the author wrote about his ventures - you can read about the creation of the strap here.

Margaret Thatcher - yes, the ex-Prime Minister Margaret Thatcher - helped invent soft serve ice cream. I’m not sure if I should be thankful or not. After Maggie graduated from Oxford in 1950, she went to work for J. Lyons and Co., a British restaurant and food manufacturing company. The team she worked on developed a way to whip air into ice cream, leaving it lighter and creamier than existing ice cream. The result? Soft serve. Yum. Photo from Carvel Brentwood.