For some reason, tuning in to a bunch of hopeful entrepreneurs as they present their crazy-smart invention ideas to the likes of Mark Cuban, Kevin O'Leary, Lori Greiner, Daymond John, Robert Herjavec, and Barbara Corcoran is deeply entertaining. Plus, it can teach some pretty important life lessons about investing—which Ree Drummond had no problem passing along to her daughter Paige during a trip to Vegas once.

Sometimes it seems like there's a lot of "I'm outs" from the cast, but the ABC show has actually discovered quite a few ingenious products in its time—and the Sharks have made some serious cash from them, too! You might be shocked at how much the humble Scrub Daddy has amassed over the years. And what about Bombas? Those top so many Christmas lists these days!

Some of the best Shark Tank products aren't even that expensive, either. Many come in around $20, making it pretty easy to add these little wonders to your cart. Take a look at some of the top-selling items from the show.

1. Loll cup

Entrepreneurs presented a new product idea that promised to alleviate one of the many concerns of parents about the health of their babies. The cups produced by the company are made of materials without phthalates and biphenyl-A, compounds widely used in the production of plastic objects that can be harmful to health. Loll land has received $ 100,000 in investment and has grossed more than $ 1 million since appearing on the program.

2. Chord buddy

The device was designed by a parent who developed the device after observing the difficulty that his young daughter had to learn to play the guitar. Chord buddy can be attached to the strings of the instrument, making it easier for beginners to learn how to move their fingers very quickly. Shark Robert Herjavec invested US $ 150,000 in the idea, in exchange for a 20% stake in the company.

3. Buggy Beds

The idea attracted the attention of the program's five judges. It is a system that can detect and prevent bedbugs in furniture, beds, and sofas. The company has already grossed more than US $ 1 million and expanded to 23 other countries after the initial investment made in the program.

4. Groove book

The application that can be used by means of subscriptions offers a more concrete record of all memories stored on the Smartphone of each user. The Groove book delivers a bound book with the chosen photos at the end of each month, for $ 2.99. The company gained 50,000 subscribers shortly after appearing on the program. In 2014, it was purchased by the printing company Shutter fly for US $ 14.5 million.

5. Wicked Good Cupcakes

The company's cupcakes are served in a jar and wrapped by hand. The sweets last up to 10 days without the need for refrigeration and can be frozen for up to six months. In the negotiation, Canadian Kevin O'Leary donated $ 75,000 to the company in exchange for $ 0.50 per cupcake sold.

6. Scrub Daddy

The company is the biggest success of all seasons of the program. The cleaning sponge created by the American Aaron Krause is rigid when used with cold water and very soft when used with warm water. In addition, the part does not accumulate odors and waste for up to two months. Lori Greiner invested $ 200,000 in the idea and Scrub Daddy has sold more than 10 million units since the Shark Tank, earning more than $ 50 million.