Why it might work: Women are unconsciously looking for a balance between boy and beast. Pre-pubescent men don't make good mates. So any bit of facial hair is a sexy reassurance. Full beards signal aggression, perhaps by calling attention to a man's jaw and teeth. Women want a bit of manliness, but not too much. A bit of stubble might be just the right compromise.

The bottom line:Think "Miami Vice," circa 1985. Don Johnson knew what he was doing.

Munch strategically.

Snacking on vegetables highlights your attractiveness and intelligence. Digging into chocolate cake shows off your fun-loving side. A 2000 studyfound that people considered a hypothetical chicken-sandwich-and-salad eater to be more intelligent and less likely to have cheated in college -- but they still preferred to socialize with someone who ordered a burger and fries. Another study of 100 college students in 1999 found that people who ate low-fat foods were seen as more attractive, intelligent and middle-class -- but also more serious, high-strung, unhappy and antisocial than folks who ate high-fat foods. Strangely, how much you eat seems to have a less clear effect on attractiveness.

Why it might work: You are what you eat, or so we subconsciously feel. Many cultures have traditionally believed that people take on characteristics of animals they eat -- think pig hearts for strength and snake tails for virility. Even in Western cultures, we ascribe "goodness" to people who eat good-for-you foods and "more fun at a party" to people who eat fun foods.

The bottom line: Eat celery at office parties and cupcakes everywhere else.

Stick around until the end of the party.

Country music fans knew it a long time ago. "Don't the girls all get prettier at closing time?" sang Mickey Gilley back in the mid-1970s. Yes, they do, and so do the men -- well, hunkier.

In a classic study in 1979, college bar patrons reported to researchers that members of the opposite sex were suddenly a lot more attractive between 10:30 p.m. and midnight than at 9 p.m. The researchers didn't factor in alcohol, however, of which there was plenty. Other, more careful studies have found the closing-time effect in drinkers and teetotalers alike, but only for those not in a relationship.

Why it might work: As the evening wanes, our chance of finding a soul mate at the party drops drastically. To feel happier about our options, we persuade ourselves that the stragglers left at midnight aren't the picked-over dregs of the party but the crème de la crème that we'd overlooked before.

The bottom line: Stick around until the last call -- but don't be surprised the next day at who you end up with.

Nuzzo is a freelance writer.