Nine blindfolded women were asked to determine, by smell alone, whether any among a group of nine men was worth pursuing.
Three men had just showered using a body wash with synthesized pheromones, three had used a body wash without pheromones, and the rest had worked up a sweat and not washed at all. They then rubbed their arms on scent strips, and handed them to the women to sniff.
— Find out what happened at Banking on a Chemical Reaction at the New York Times. Many thanks to Jessica for the link!