The California Milk Processor Board launched a scent marketing scheme in 2006 to accompany its "Got Milk?" campaign. The city of San Francisco called for an immediate removal of the cookie-scented strips after complaints.

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Scent Marketing

Advertisers are eager to cash in on the close link between smell, memory and mood. Real estate agents have long used scent marketing as a way of putting clients at ease. Sellers set fresh pie or cookies on countertops to make a house seem comfy and livable. But because there's a limit to how many pies one agent can bake, companies that sell aroma-marketing systems are stepping up. Housing developments, hotels, stores and even car manufacturers are turning to customized scents to help set a mood and maybe even make an impression.

Scent marketing is the latest trick to stand out from the visual and auditory barrage that dominates advertising. These scents, however, are a far cry from the strong smells of incense and patchouli at the bead store. They're subtle and almost imperceptible to the unwitting sniffer. Developers use carefully tuned scents to lure customers into a sense of well-being. Stores that sell shoes or shirts, items ideally not associated with odor, formulate aromas of ivy or crisp linen. Some companies even strive to develop a "brand scent," something that customers will associate with the company as much as a logo.

To learn more about smell and the other senses, sniff out the links on the next page.