BOSTON (AP) - Deborah Anderson had heard the urban legends about the contraceptive effectiveness of Coca-Cola products for years.

So she and her colleagues decided to put the soft drink to the test. In the lab, that is.

For discovering that, yes indeed, Coke was a spermicide, Anderson and her team are among this year's winners of the Ig Nobel prize, the annual award given by the Annals of Improbable Research magazine to oddball but often surprisingly practical scientific achievements.

The ceremony at Harvard University, in which actual Nobel laureates bestow the awards, also honored a British psychologist who found foods that sound better taste better; a group of researchers who discovered exotic dancers make more money when they are at peak fertility; and a pair of Brazilian archaeologists who determined armadillos can change the course of history.

Anderson, a professor of obstetrics and gynecology at Boston University's School of Medicine, and her colleagues found that not only was Coca-Cola a spermicide, but that Diet Coke for some reason worked best. Their study appeared in the New England Journal of Medicine in 1985.

"We're thrilled to win an Ig Nobel, because the study was somewhat of a parody in the first place," Anderson said, adding she does not recommend using Coke for birth control purposes.

A group of Taiwanese doctors were honored for a similar study that found Coca-Cola and other soft drinks were not effective contraceptives. Anderson said the studies used different methodology.

A Coca-Cola spokeswoman refused comment on the Ig Nobel awards.

Duke University behavioral economist Dan Ariely won an Ig Nobel for his study that found more expensive fake medicines work better than cheaper fake medicines.

"When you expect something to happen, your brain makes it happen," Ariely said.

Ariely spent three years in a hospital after suffering third-degree burns over 70 percent of his body. He noticed some burn patients who woke in the night in extreme pain often went right back to sleep after being given a shot. A nurse confided to him the injections were often just saline solution.

He says his work has implications for the way drugs are marketed. People often think generic medicine is inferior. But gussy it up a bit, change the name, make it appear more expensive, and maybe it will work better, he said.

Charles Spence's award-winning work also has to do with the way the mind functions. Spence, a professor of experimental psychology at Oxford University in England, found that potato chips - "crisps" to the British - that sound crunchier taste better.

His findings have already been put to work at the world-famous Fat Duck Restaurant in England, where diners who purchase one seafood dish also get an iPod that plays ocean sounds as they eat.

Geoffrey Miller's work could affect the earning potential of exotic dancers everywhere.

Miller, an associate professor of psychology at the University of New Mexico, and his colleagues knew of prior studies that found women are more attractive to men when at peak fertility. So they took the work one step further - by studying earnings of exotic dancers.

In the 18 subjects Miller studied, average earnings were $250 for a five-hour shift. That jumped to $350 to $400 per five-hour shift when the women were their most fertile, he said.

"I have heard, anecdotally, that some lap dancers have scheduled shifts based on this research," he said.

Armadillos helped win an Ig Nobel for Astolfo Gomes de Mello Araujo, a professor of archaeology at the Universidade De Sao Paulo in Brazil, and a colleague earned.

Pesky armadillos, they found, can move artifacts in archaeological dig sites up, down and even laterally by several meters as they dig. Armadillos are burrowing mammals and prolific diggers. Their abodes can range from emergency burrows 20 inches deep, to more permanent homes reaching 20 feet deep, with networks of tunnels and multiple entrances, according to the Humane Society of the United States' Web site.

Araujo was thrilled to win. "There is no Nobel Prize for archaeology, so an Ig Nobel is a good thing," he said in an e-mail.

Here is the list of 2008 Ig Nobel winners, awarded Thursday at Harvard University by the Annals of Improbable Research magazine:

NUTRITION: Massimiliano Zampini and Charles Spence for demonstrating that food tastes better when it sounds better.

PEACE: The Swiss Federal Ethics Committee on Non-Human Biotechnology and the citizens of Switzerland for adopting the legal principle that plants have dignity.

ARCHAEOLOGY: Astolfo Gomes de Mello Araujo and Jose Carlos Marcelino for showing armadillos can scramble the contents of an archaeological dig.

BIOLOGY: Marie-Christine Cadiergues, Christel Joubert and Michel Franc for discovering that fleas that live on a dog can jump higher than fleas that live on a cat.

MEDICINE: Dan Ariely for demonstrating that expensive fake medicine is more effective than cheap fake medicine.

COGNITIVE SCIENCE: Toshiyuki Nakagaki, Hiroyasu Yamada, Ryo Kobayashi, Atsushi Tero, Akio Ishiguro and Agota Toth for discovering that slime molds can solve puzzles.

ECONOMICS: Geoffrey Miller, Joshua Tyber and Brent Jordan for discovering that exotic dancers earn more when at peak fertility.

PHYSICS: Dorian Raymer and Douglas Smith for proving that heaps of string or hair will inevitably tangle.

CHEMISTRY: Sheree Umpierre, Joseph Hill and Deborah Anderson for discovering that Coca-Cola is an effective spermicide, and C.Y. Hong, C.C. Shieh, P. Wu and B.N. Chiang for proving it is not.

LITERATURE: David Sims for his study "You Bastard: A Narrative Exploration of the Experience of Indignation within Organizations."

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Source: Annals of Improbable Research.