Dianna Hamilton has five children and works as a data analyst for UnitedHealth Group, so she doesn't have much time to volunteer.

Now she doesn't need much.

Last year she was asked to take part in a pilot program in which the Minnetonka-based company's employees become "micro-volunteers." Working online in intervals as short as 15 minutes, they use their job skills to help nonprofits brainstorm marketing ideas, design logos, proofread brochures, build databases and much more.

"It's a great idea," Hamilton said. "I love the idea of doing these small, short-burst projects, especially if you can do them online and at work."

Micro-volunteerism is a relatively new workplace trend but is already becoming a powerful "employee engagement" tool, some human resources managers say.

Target, Kraft Foods, IBM, Microsoft, Deloitte and scores of other corporations are climbing on board by tapping online micro-volunteer catalysts such as Sparked.com, Catchafire.com and the Points of Light Institute's A Billion + Change campaign.

UnitedHealth, the nation's largest health insurance company, piloted the idea internally last year and had 230 employees sign up to donate $50,000 worth of time.

"This platform is so cool. It's so smart," said Kate Rubin, vice president of social responsibility and president of the United Health Foundation.

The company sees the pilot program as a logical extension of its efforts to encourage workers to volunteer, with more than 5,000 employees donating 169,000 hours of time last year. Just last week, 200 employees got together in Minneapolis to build bikes for poor children.

That project took two hours -- time that Hamilton says she just doesn't have.

Today Hamilton is UnitedHealth Group's leading participant in the micro-volunteering pilot. She's done projects worth $4,000 in 15 to 30 minute intervals. She built an Excel spreadsheet to tally scores for a fencing club; proofread marketing brochures for another nonprofit; crafted a pet walk fundraiser for a pets-of-deployed-vets program, and created a database of children's cancer facilities in Denver and New Mexico for another nonprofit.

Before the pilot program, Hamilton said, volunteering "took a boatload of time and you have to be in a physical location for an extended period of time. That's very hard when you have kids. But this was easy and fun and didn't take me a lot of time. I love it."

Doing good, minus stress

Kraft launched its micro-volunteering program one year ago. Company spokeswoman Julia Fernandez found that employees were happy to help others without stressing out over traffic, scheduling or time.

Since then 400 employees signed on in the United States, France, England and Australia. So far they've helped 130 nonprofits in seven countries.

"It's an ideal way for employees to give back by putting their professional skills and personal interests to use," Fernandez said.

Sparked.com and Catchafire .com link corporate employees with budget-strained nonprofits. Billion Plus gets pledges from companies looking to boost their number of employee volunteers.

They let the involved companies take it from there, but keep tabs on their hours of volunteer projects. While micro-volunteering started in fits and starts in 2008, it's since fanned from coast to coast and beyond.

UnitedHealth employees use Sparked.com to sign up for quick online projects that have helped groups that trained seeing-eye dogs, counseled victims of violence, coached people with autism and fed the poor.

ABillionPlusChange.com started as a federal program in 2008, but it relaunched in November and is run through the Points of Light Institute. Since November, A BillionPlus has amassed corporate volunteer pledges worth $1.7 billion in employee time over the next three years.

'Not quite proven yet'

"Micro-volunteering is one piece" of that equation, Executive Director Jenny Lawson said. "It is a type of volunteering that is increasingly interesting to companies. But it's a model that is not quite proven yet, so everyone is still learning how to do it."

Still, A Billion + Change has more than 100 corporate volunteers and more than 100 nonprofits who are benefiting from $1.7 billion worth of employee's time, including micro-volunteering. Its goal is $2 billion.

It sounds noble. But not everyone was immediately sold on the idea.

When some of these efforts first launched, "It was all of this kind of breathless excitement and press releases and this 'Oh my God, this is amazing' [type of promotion]," said Kate Barr, executive director of the Nonprofits Assistance Fund in Minneapolis. "I was intrigued enough to download the app. But it was so lame-o, lame-o, lame-o."

Barr recalls one environmental group saying that volunteers could help by taking a picture of trash. "All I could think was, 'Really?'"

Fast forward a few months. Today Barr says, "Right on. Why not? Maybe there is a value."

"Corporations are always looking to get their employees involved," she said. "But we tend to overwork our employees. So the idea of giving 10 minutes of time to a good cause, we kind of like that."

Dee DePass • 612-673-7725