Six ambitious visions for a better tomorrow. Six unusual models for combining profits with social good. But in the end there could be just one winner of the Inc. + Toms Pitch for Good competition.

Or not. "We've decided to change it up a little bit," said Blake Mycoskie, founder of the virtuous shoe-giving company, Toms. "Instead of giving one company $100,000, we're going to give two companies $50,000."

Mycoskie had latitude to modify the rules. His company's Social Entrepreneurship Fund is investing in the winners, which were chosen this evening during a Shark Tank-style competition held at Inc.'s Growco Conference, in Las Vegas.

The winning companies take dramatically different approaches to improving people's lives through business. Their founders, too, could not be more different.

Anna Stork and Andrea Sreshta met as graduate students in architecture at Columbia University. In response to the 2010 earthquake in Haiti, they designed an ultra-lightweight portable lantern that recharges in the sun. Chicago-based LuminAid's goal is to help "the more than two billion people around the world that lack stable and safe access to electricity, especially after disasters," explained Sreshta, as her two minutes of allotted time ticked down on giant screens abutting the stage. "With a light in hand, kids have something by which to study at night. Women who are left more vulnerable in the wake of disasters report feeling safer, and their families comforted."

Coss Marte, who presented first, also came up with the idea for his business while living in New York. But he wasn't at some Ivy League college. He was serving time for drug dealing at Greene Correctional Facility, about 30 miles south of Albany. Obese and scared of dying in prison, Marte developed a workout routine that could be performed in a cell, and taught it to other inmates, who also lost weight. Today, in a studio in lower Manhattan, he teaches the program to (chiefly) Millennial women. "I hired the most bad-assed instructors straight out of prison," said Marte, who plans to build a chain staffed by ex-offenders. "With national expansion, we can help reduce the recidivism rate, which is at an all-time high of 76 percent."

Joining Mycoskie on the judging panel were Danae Ringelmann, co-founder of Indiegogo, and Chinedu Echeruo, founder of Gigameet. Grilling each contestant after their presentations, the judges asked as many questions about margins and competitors as about social impact, seeking winners equally adept at making money and making a difference. "We were really impressed with the different type of social effect everyone was making," said Ringlemann. "There are a lot of problems out there, and everyone was tackling them head on."

The other finalists, chosen from roughly 275 applicants, were CommuniGift, a business that encourages the friends and families of birthday children to buy gifts, instead, for a child in need; DayOne Response, which makes a bag for collecting, transporting, and purifying water that can be used after disasters; and Ethic, an automated investment platform that allows users to create portfolios of businesses that reflect their values. Lucky Iron Fish, which makes fish-shaped ingots that, when added to cooking water, reduce iron deficiencies, was the audience favorite in voting that took place while the judges were making their decisions off-stage.

In addition to the money, both winners will be promoted on Toms' and Inc.'s social-media platforms, will be featured in Inc.'s Positive Energy column, and will receive mentoring from several successful entrepreneurs.

"We couldn't be more excited," said Sreshta about LuminAid's win. "Somewhere in the back of our minds we've always asked the question: Well, what would Toms do? So it's really come full circle on a day like today."

LuminAid already had validation from high-profile entrepreneurs: all five Sharks wanted in when Sreshta and Stork appeared on Shark Tank last year, and Mark Cuban invested $200,000. ConBody's Marte sounded more surprised. "I thought I was going to lose because [Mycoskie] said he wanted companies that he could help and I'm like, I don't have a product," said Marte. "When I heard my name I was like, 'Oh, my god.'"

Prior to the contest, we asked visitors to to vote for their favorite finalists. Check out readers' top votes