From the August 2008 issue of Entrepreneur

Expectant parents can log on to maternity clothing retailer Due Maternity's website and download a clock that will tick away the minutes until their bundle of joy is due. Mac users needing divine inspiration can head over to Logos Bible Software and install easy-access Bible verses.

These are just two examples of the growing use of widgets--small software programs that perform a specific function--as marketing tools. "We think about widgets in two different categories," says Liza Hausman, vice president of marketing at Gigya Inc., a widget development and distribution company. "There are utility widgets, like calendars or other tools, [that] you put on a start page or desktop [and] are strictly useful. The other group is social media widgets, which are more likely to be placed on a profile page in a social network or on a blog." Either way, widgets can be valuable marketing tools, giving brands an effective way to engage with customers and prospects.

That's exactly what Albert DiPadova, 39, co-founder of San Francisco's Due Maternity, found when he noticed a decline in the effectiveness of his e-mail newsletters because customers saw them as just another "thinly veiled generic offer." He and his wife and co-founder, Shannon, 36, decided to create a widget that would reso-nate with customers of their $3 million company. Within seven months, the countdown clock--which features pop-ups suggesting activities and products related to the customer's point in her pregnancy--had been downloaded more than 30,000 times and had a conversion rate of 5 percent.

Bellingham, Washington-based Logos Bible Software, a $16 million Bible software publisher, used a widget to promote the launch of its Mac-based software line. This resulted in a steady stream of downloads. "We knew not everyone wanted to give their contact info away, [so] we uploaded the widget to as many shareware/freeware sites as we could find," says Dan Pritchett, 35, who co-owns Logos Bible Software with his brother, Bob, 37, and their father, Dale. "Today, if you search 'Logos Bible widget,' there are almost 5,000 pages that reference it, and perhaps 50,000 or more users that have it installed."

Developing a widget can cost as little as $5,000 and can rise exponentially based on its complexity, says Hausman. The key to a successful widget is to get the word out and encourage downloads. She adds, "Create something that's relevant and makes customers want to interact with you."

Gwen Moran is co-author of The Complete Idiot's Guide to Business Plans. Reach her at gwen@gwenmoran.com.