Simple business ideas that made millions -

Every product you own was, at one point, just a simple idea. It was conceptualized by someone, who then turned it into a business, and eventually made money from it. 

Many business ideas might sound absurd at first, and indeed many people are heavily skeptical about some of them. But sometimes, entrepreneurs do have the last laugh.

Not every idea works, but some of those that do, didn't necessarily sound great when they were first pitched. Imagine someone telling you that they were going to become rich by selling rocks as pets? You would most likely burst out laughing and think of it as some sort of a joke, right? Well, one man didn't agree and proved everyone wrong. 

Many seemingly wacky ideas turned into multimillion-dollar businesses. Simple (yet genius) ideas made a whole bunch of new millionaires.

Curious to see how these entrepreneurs made their millions? Click through.

© Shutterstock

Pet Rock - Don't have the time or patience to take care of a living pet? Pet Rock is the answer. Gary Dahl had this brilliant idea of selling seemingly common rocks in a nice package. He became a millionaire.

© Public Domain

Upside-down bottle -

We now take these for granted, but Heinz revolutionized the food industry in 2002 with this mess-free squeezable plastic bottle.

© Shutterstock

Post-it Note - Despite technological advancements, these sticky labels can still be spotted in most offices around the world.

© Shutterstock

Band-Aid - Since the 1920s, these adhesive bandages have been a staple in every household's first aid kit.

© Shutterstock

Loom bands - These turned everyone into bracelet makers. A peg board is used to craft a variety of things with these small rubber bands.

© Shutterstock

Smiley - The yellow smiley face was invented by Harvey Ball in 1963. Currently, the Smiley Company holds rights to the symbol in over 100 countries, excluding the US.

© Shutterstock

Velcro - One of the world's most popular fasteners was introduced in the market in the 1950s. Needless to say, it was—and still is—a huge success.

© iStock

Hula Hoop - A huge fad in the 1950's, the Hula Hoop has continued to be used for many years, not only as a toy, but also as a prop in circus performances and gymnastics.

© iStock

Slinky - This classic spring toy was invented by Richard James in 1943. Millions of units have been sold since then.

© iStock

The Million Dollar Homepage - Alex Tew decided to pay his way through college by selling advertising space on his website for US$1 a pixel. It went viral and every company wanted to have their name on the site.

© Reuters

Chia Pet - This one is perfect for those looking to upgrade from a pet rock. The company sells these figurines, used to sprout chia, in many shapes and forms. They've been around since the early '80s and are still relevant today.

© Shutterstock

Tamagotchi - This "digital pet" was huge in the '90s. So much so that, up until 2017, over 82 million units had been sold.

© Shutterstock

Crocs - Initially developed as boat shoes, Crocs quickly became a craze and millions of pairs were sold.

© Shutterstock

Crazy Straws - How to make your kids drink more water? Make it fun! 

© iStock

Beanie Babies - How to put a spin on your average soft toys? Stuff them with plastic pellets and make them collectible. 

© Shutterstock

Trunki - Kids finally had a reason to carry/ride their luggage. Trunki made travelling fun for children. 

© Shutterstock

Santamail - With so many children writing to Santa every Christmas, this company registered a postal code at North Pole in Alaska (US) and started charging US$10 per letter from Santa Claus.

© Shutterstock

Doggles - Goggles for dogs, really? Yes, dogs also need eye protection in certain circumstances, hence the success of the product.

© Shutterstock

Plastic Wishbones - You no longer had to eat a turkey in order to pull a wishbone apart. The plastic version was a big commercial success.

© Shutterstock

Koosh Ball - You're probably familiar with this rubber toy ball. Scott Stillinger found a gap in the market for a ball a small child could catch, but soon it turned into a fad and he sold millions of units.

© Shutterstock

Snuggie - A blanket you can wear? Sounds great! And a lot of people thought the same when they were introduced in late 2008.

© Reuters

Furby - The Furby frenzy of the late 1990s saw a few revivals throughout the years. It's still one of the most popular toys ever. 

© iStock

Billy Bob Teeth - Fake, crooked, rotten teeth have a place in the market. So much so, that Billy Bob Teeth Inc made over US$50 million in profit selling these.

© iStock / Shutterstock

Slap Bracelets - In 1990 alone, Stuart Andrews—the man who invented the bracelets—made between US$6 million and US$8 million selling these.

© Shutterstock

Magic 8 Ball - In the 1950s, this was the go-to toy when you needed to make a decision—the ball would always have an answer... though you might have needed to ask it a little later.

© Shutterstock

PositivesDating.com - There was a gap in the online dating  market for HIV-positive people who were trying to find love. This website filled the gap.

© iStock

Vocation Vacation -

Would you pay to work on vacation? Many people do, and they work at their dream job too! The site allows people to try different jobs while on vacation. Crazy, right?

See also: These German inventions upgrade your everyday life

© iStock