Get within one hundred feet of the Scharffen Berger factory on a weekday morning, and your nose is likely to get a wakeup call. The air in this otherwise nondescript patch of industrial West Berkeley is dusted with the wafting smell of pure milk chocolate. If you can't imagine the aroma, just think of watching Charlie and the Chocolate Factory in Smell-o-Vision. It's worth rolling down the windows if you're driving by, but the chocolatey bouquet is best appreciated al fresco. If you're on foot or on a bike, you might find yourself stopping to inhale the aroma of pure airborne cocoa for a few nostalgic moments. If a quick sniff doesn't fix you, the factory offers free tours three times a day. Or you can get the smell to go. Pick up some Cacao, "a hand crafted chocolate perfume for men and women," made with Scharffen Berger's own cocoa beans, at only $140 a quarter-ounce.