Corporate America's worst nightmare lives in a tiny one-bedroom apartment, loves browsing in flea markets and has a lop-eared brown and white pet rabbit named Crackers.

Meet Molly Katchpole. The 22-year-old Washington, D.C. resident has recently tangled with a couple of billion-dollar corporations, and cowed them into submission, without breaking a sweat.

Take Verizon Wireless, which had planned a $2 "convenience" charge for the privilege of paying a bill by phone or online. Katchpole, a Verizon user for eight years, was offended by the very idea that loyal customers could be penalized for paying what they owed. So she went on the website http://Change.org - organized a petition - and watched as it quickly racked up more than 165,000 signatures. As consumer outrage went viral, Verizon backpedaled within hours.

And how about Bank of America's infamous $5 monthly usage fee for debit cards? It too was kiboshed, partly thanks to another Katchpole petition and 300,000 of her outraged brethren, at a time when the Occupy Wall Street movement had been pressuring banks.

"I'm not exactly sure what these companies are thinking," says Katchpole, who only graduated last spring from Roger Williams University in Rhode Island and now works as a fellow at the nonprofit Rebuild the Dream, an organization that lobbies against income inequality (her petitions are personal ventures, unrelated to her job).

"It's so out of touch with reality and hurt their customers are going through. My Verizon petition was only up for about eight hours before they backed down."

Also forced into a recent and embarrassing climbdown was video-streaming company Netflix, which had planned to spin off DVD rentals into a stand-alone service called Qwikster. User objections became so deafening that the notion was killed before launch.

"The Internet is the great equalizer, and that's a beautiful thing - even if it's not positive for us," said Netflix spokesman Steve Swasey. "We made mistakes that hurt our brand, consumers let us know about it, and now we're rebuilding step by step."

Such is the growing power of social media, which can make consumer complaints go viral and cause serious brand damage within days or even hours. While one person can't topple a company, if that person is able to assemble an army of hundreds of thousands behind them, they become a force to be reckoned with.

Thanks to the increasingly savvy use of tools like Facebook and Twitter, the power balance between company and customer has been tilting in the latter's favor.

Read more on: As consumer power goes viral, company branding quakes