In the spring of 2008 Kris Wittenberg was out at lunch in her small town of Eagle, Colo., when a woman was rude to her. Looking back, she can't remember the exact details. "I just remember coming back to my office and wondering why people can't just be good to people," she says.

The proverbial light bulb went off. Wittenberg, who runs a successful promotional products company, SayNoMore! Promotions, vowed to put "Be Good to People" on a T-shirt. In a moment of inspiration she went to GoDaddy.com to see if the website was available; much to her surprise, it was. "I bought it that moment," says Wittenberg, who also began the process of trademarking the slogan.

Despite her initial flurry of inspiration, it took Wittenberg nearly a year to finally make that T-shirt. At the time, her promotions company, which she runs with her husband, August, was generating more than $1 million in annual revenue and on track to double sales from the previous year. "I just didn't have time for another business," she recalls.

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That changed later that year when the pharmaceutical industry -- a major chunk of their business at the time -- agreed to stop giving out logoed pens, pads and other goodies. "Seventy-percent of our business was gone," says Wittenberg. The recession, meanwhile, didn't help matters.

To add to their string of bad news, the Wittenbergs were sued by their homeowners association for a parking area related to a home addition (the suit was settled out of court and they were cleared of wrongdoing). The night before a meeting with the HOA, Wittenberg made a homemade Be Good to People T-shirt out of iron-on letters. "The meeting went horribly," she says, "but I had three people ask me where I got that T-shirt."

That's when Wittenberg began working on Be Good to People in earnest, ordering dozens of different products, from T-shirts and tumblers to blankets and satchels, all printed with the same mantra. Everything is in black and white, says Wittenberg, because the message is a fundamentally simple one.

When Wittenberg began selling the goods at weekend markets in nearby Minturn and Vail, sales were brisk. "People would buy four or five things and then come back and buy more," she says. Wittenberg also signed up a couple dozen independent retailers around the country. It wasn't enough to carry them through financially -- but Wittenberg says it reignited her passion as an entrepreneur, which she credits for helping SayNoMore recover more quickly. "In 2010 we were back to where we were and have grown ever since," she says.

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These days Wittenberg is working on handing over more of her day-to-day duties at SayNoMore to her husband and half a dozen employees. "Ideally, I'd like to focus more of my attention on building out BGTP," she says. Online sales are currently a small chunk of Be Good's business, though it has nearly 19,000 followers on Facebook. When bad things happen in the world, she adds, activity typically picks up, though it doesn't necessarily translate to sales.

Wittenberg is now speaking with investors and exploring alternative funding options. She'd like to build up her inventory, revamp the website and eventually take the concept global. "My vision is wherever you are in the world you'll see Be Good to People," she says, adding that her goal is to make it as ubiquitous as the smiley face was in the 1970s.

In the meantime, Wittenberg says that wearing Be Good to People garb has been an interesting social experiment. "I always wear BGTP when I travel, and I've met people because of it and even gotten upgrades I don't think I would have gotten otherwise," she says.

At the same time, having the slogan in front of her all day, she adds, has helped calm her usually intense personality. "We call them magic shirts because you put on a shirt and you're nicer," she says. "You can't wear your Be Good to People shirt and be a jerk."