It was 2008, and Matt Williams was a college student at Villanova when the light bulb went off in his head at a bar one night. In a bathroom. "I put my beer down on the urinal, like I always do, and water from the flush valve dripped in," says Williams. "I was kind of grossed out, but also thinking about drinking it."

Matt Williams

He noticed every other guy in the bathroom was also trying to balance a beer on the urinal, on the floor, in a pocket or holding it between his teeth. "I walk out, and I see a line by the bathroom," he says. "Everyone in line is carrying beer, the women are carrying purses walking in, and I'm like, 'This is crazy. Why isn't there a functional piece in the bathroom?'" Williams imagined a simple shelf next to toilets or urinals that could hold a beer, phone or pocketbook. Then he got a second idea. While in the bathroom, he noticed a newspaper tucked above the urinal. He was reading it as he stood there, a captive audience. Hmmmm. He needed a shelf for his beer. He was looking at something while he stood there. "How can we marry the two?" Williams asked himself. What if he created a shelf that held advertising? Williams walked back to his seat at the bar, wrote his idea down on a napkin, then immediately left. "I was like, 'I can't get too drunk here tonight. I need to remember this idea.'" Over the next few months, the idea percolated in Williams' young brain. He'd always been an entrepreneur — at the age of 10 he would buy unsold size 14 Jordans from local shoe stores, reselling them for top dollar on Ebay; at 16 he attempted to patent a scratch-resistant CD. He was the type of person who always saw problems that need solutions. "I can come across as very pessimistic sometimes, when I'm complaining when a door opens one way, when I think it should open the other," he says. "I'm like, 'Why am I carrying groceries and this door pulls and doesn't push? Don't they know that people are walking out with stuff?'" Williams scraped together $65,000 by maxing out credit cards and borrowing from his dad and two investors. He used the money to hire an engineering firm that developed a prototype for his beer shelf. He named the product LavCup, with the tagline, "Because you can't hold it."

The LavCup

The LavCup is a small shelf with a non-stick rubber mat, plus an antimicrobial silver ion built in to keep it sanitary. There's a locked slot to hold advertising — locked because Williams learned the hard way that inebriated fans sometimes like to break in and steal the ads. He started marketing the product in 2013, flying himself to sports-related conferences. "I just started showing up, 'All right, who are the decision makers? Where are they going to be?'" His first encounter was with Peter McLoughIin, president of the NFL's Seattle Seahawks. It did not start off well. "He was coming down the escalator, and I said, 'Peter! Peter! I have to show you something on my iPad. You're going to like it!'" Williams, now 32, recalls. "I'm not going to say exactly what he said to me, but he's like, 'I'm in a rush. I have to get on a plane.'"

Peter McLoughIin, president of the NFL's Seattle Seahawks, gave LavCup its first big break. Getty Images | Jesse Beals/ Icon SMI/Corbis

Williams persisted. "I was like, 'Peter, please, like 30 seconds. I need 30 seconds of your time!' I just showed him my iPad. I said, 'This is what I invented.'" McLoughlin was no longer angry. "He's like, 'Oh my gosh, this is brilliant.'" Within 10 weeks, LavCup had its first big order, 1,200 units for CenturyLink Field, where the Seahawks play. Williams called it "the beginning of the snowball." LavCup now has more than 21,000 units installed in 26 venues covering every major sports league. Another 35 venues are pending. The business has raised more than $600,000 from 10 investors, and Williams says 2017 revenues hit $2 million. He's looking to move into new areas like movie theaters and cruise ships.

CNBC special correspondent Jane Wells trying out the LavCup

Here's how the business model works: LavCup doesn't actually sell the shelves. They're given to stadiums and arenas for free, and then the company creates and sells advertising on the shelves, splitting revenues with the venue. Williams loves making his own ad content for the shelves, especially since they're in restrooms. "Everyone's used to seeing DUI attorneys and strip clubs and local dingy advertisers that are willing to pay money to be in front of people," he says. "We're turning that on its head, and we're saying, 'No, fans actually want to engage with this.'" For example, LavCup was paid to promote a product in connection with an upcoming Katy Perry concert at a particular stadium. "We were saying, 'Savings that'll make you roarrrrr,'" referencing Perry's similarly titled song. "Really corny, funny as hell," he laughs. The LavCups are installed to take a beating, literally. And they hold up pretty well. Williams demonstrated their durability by punching several installed in a men's room inside FedEx Field, where the NFL's Washington Redskins play. One by one, the shelves survived his punches ... until one suddenly popped out from the wall. Williams started laughing hysterically (so did this reporter), before explaining that it had been poorly installed in the drywall. "It will happen," he laughs. Williams is a big believer in simple, low-tech products. In fact, he's expanded into a side business distributing fortune cookies, sending out 100 million cookies a month to 10,000 Chinese restaurants and selling ad space or coupons on the backs of the fortunes. "There are so many untapped spaces for advertising," he says.

Fortune cookie advertising