A University of Michigan survey revealed surprising results: nearly 28 percent of men and nearly 15 percent of women had bartered sex for a variety of goods and services, including football game tickets, food, tutoring services and even help with the laundry.

It's not because they were lacking the resources to pay for their wants and needs. The article quotes Daniel Kruger, research scientist at the University of Michigan School of Public Health: "The students surveyed "recognized the value of this socioeconomic currency system." He published his findings in the April issue of "Evolutionary Psychology."

Before you think that bartering sex for stuff or services is limited to the college crowd, think again. Several professionals interviewed for the article reported they had been solicited by clients, and offers of sexual pleasure took place.

Dr. Chris Fariello, director of the Institute for Sex Therapy at the Council for Relationships, is quoted as saying "Call it crass, sexist or gender stereotyping all you want, but there are thousands of years of biological programming at work here."