According to a new study, there's actually some scientific basis for those old Folgers commercials, which showed people perking up when they got a whiff of coffee brewing.

Psychology and business researchers at Toronto University in Canada and Monash University in Australia have discovered that the smell of coffee provides a placebo effect that causes spikes in "ambition, focus, and arousal" -- even before you get the stuff in your gullet.

That's not sexual arousal, mind you -- just general alertness.

"So walking past your favorite café, smelling the odors of coffee grounds, or even witnessing coffee-related cues in the form of advertising can trigger the chemical receptors in our body enough for us to obtain the same arousal sensations without consumption."