By Lisa Cohen, CNN

Editor's Note: How can individuals help combat modern day slavery? Watch "Taking a Stand, Making a Difference".

Denver, Colorado - Staring down a mountain of bras in her basement, Kimba Langas knew things had gotten out of hand.

The stay-at-home-mom started collecting unwanted bras as a way to help women on the other side of the world. It started small through word of mouth, and then a Facebook page.

But the bras quickly overran her home in suburban Denver, Colorado. They were in her basement, in her garage, in her car. They were in bags, in boxes, in envelopes. Her husband, Jeff, tried to navigate his way around them, but it wasn't easy.

"He was constantly moving boxes out of his way to access his tools," Langas said. "Down in the basement is where he keeps his table saw and other large tools, so besides having to move boxes, he would suffer a scolding from me from getting sawdust all over the bras!"

And the neighbors were beginning to talk, too. "If the weather's nice I usually count and box up bras in my garage," Langas said. "The neighborhood boys who are always around playing in the cul-de-sac try to pretend they're not watching!"

Langas collects unwanted bras for a charity called "Free the Girls" which gives them to young women coming out of sex trafficking in Mozambique - not to wear, but to sell in used clothing markets where bras are a luxury item and command top dollar.

The girls can make three times the average wage, more than enough to support themselves and not be trafficked again.

Sitting in her living room packing boxes of bras with her four-year-old son, Wyatt, she reflects on how quickly the little project took off.

It was the pastor of her church who came up with the idea for "Free the Girls." He was planning on moving to Mozambique for missionary work, and called Langas to see if she would run the project with him. She thought it sounded like fun.

"One of the things that was so appealing to me for "Free the Girls," besides the catchy name, was donating bras," she said. "I had probably five or six bras in the back of my drawer. As women, you know, we buy a bra, don't try it on, get it home, wear it once, it doesn't fit. And it's one of those items where you'd like to donate it when you donate clothes to a charity, but you're not sure. Do we donate bras? What do we do with bras?"

Apparently, that sentiment resonated with women across the U.S.. Shortly after launching the Facebook page, the bras started coming. The response was much bigger than she expected.

"I remember in the beginning how excited I would get to pick up envelopes and small boxes, and wow, if a box had 50 or even 100 bras that was crazy," Langas said. "And all of us of sudden, you know, 800 bras, 1,000 bras, 1,250 bras.

"There was a drive in Arizona and the women collected 8,000 bras. There's a church in Tennessee that collected 3,000 bras. There's a group here in Denver that collected 1,250 bras. It's just one of those things that caught on and spread."

It spread so much that Langas had to rent a storage unit to hold them all. But now she has a big problem: How is she going to move 25,000 bras 10,000 miles (15,000 kilometers)?

A shipping container would cost $6,500; money she says she just doesn't have. When she hears about people traveling to Mozambique, she asks them to take an extra suitcase with them, filled with bras. But her goal is to raise enough money to ship all of them.

In the meantime, she is encouraged by the volunteers helping her and motivated by the young victims she is fighting for, happy to do her small part in the fight to end modern-day slavery.

"Eventually it is going to change," she says. "I know it is. And if it's not in my generation, I hope that my son gets to see major change and I hope, by the time he's out of college or maybe even my age, hopefully sooner, he will be like, "Slavery? What? Oh, I read about it in my textbook."