Many of the entrepreneurs who appear on Shark Tank implore the show's investors to inject money into their company because they can disrupt industries or make lives easier with their product. 

Two of the contestants that appeared on Friday's episode of the ABC show, Van Gould and Chris Sheldon, had a slightly different proposition: they wanted the sharks to help their company, NoPhone, become the Pet Rock of modern era.

The Pet Rock may be the butt of many jokes, but its inventor, Gary Dahl, sold nearly 1.5 million Pet Rocks in a matter of months in 1975, according to The New York Times. Gould and Sheldon's Pet Rock contender: a fake phone for people addicted to real phones.

Gould and Sheldon, who both work in advertising, didn't so much pursue entrepreneurship as they did stumble into it. They were at a rooftop bar with a couple of friends in the summer of 2014, and noticed that nearly everyone at the bar was glued to their phones. They started bouncing half-baked ideas off one another about what they could do to cure phone addiction, and came up with the idea for a rectangular piece of plastic that looks and feels like a phone, albeit with no high-tech features.

Gould, Sheldon, and two other friends--Ingmar Larsen and Ben Langeveld--came up with a name for their fake product: NoPhone. They even launched a website, primarily with the intention of passing it around to a few friends to generate some laughs. But they started receiving hundreds of emails from people with real interest in buying the NoPhone. 

"Some people just started sending us their credit card information, which I thought was ridiculous," Sheldon says.

They quickly realized that they had the potential to make a serious payday if they created a real NoPhone. In November 2014, they launched a Kickstarter campaign for the NoPhone, which raised about $18,000. In total they've received nearly 6,000 orders combined for both the original $12 NoPhone, and the $18 NoPhone with a "selfie upgrade" (meaning that it contains a mirror). 

While the NoPhone gave the sharks a laugh, they weren't impressed with Gould and Sheldon's business acumen. 

"There's only one thing I hate more than people staring at their phones, and that's dumb patents," said tech billionaire Mark Cuban, after learning that Gould and Sheldon had applied for a provisional patent on the NoPhone. "What's really dumb is a patent on a block of plastic."

"It's never going to be a big business," added venture capitalist Kevin O'Leary.

Not all of the entrepreneurs that have appeared on the show with a tongue-and-cheek product have walked away empty handed. The co-founders of Ilumi Bowl, a motion-activated night light for the toilet bowl, scored a $100,000 investment from O'Leary earlier this year after they explained how they could expand the company's product line, and create lights that projected different images and videos as well as neon-colored lights.

But Gould and Sheldon are the first to admit that they have no idea where the NoPhone will go from here. They are looking into selling the NoPhone in novelty stores, and creating a companion product--the NoTablet. They say that they plan to continue to make the NoPhone as long as the demand exists.

"We would have never thought that five years ago, people would be this addicted to their phones, and would need a NoPhone," Sheldon says.