Eva Pasco, who loosely based her novel Underlying Notes on her fragrance addiction, has boxes and trunks and specially made cabinets all over her house for her perfume collection. She calls herself a "fragrance floozy," but she's no eccentric kook. At least half a million people like her subscribe to blogs like Sniffapalooza and Now Smell This, virtual clubhouses for those who love perfumes, particularly hard-to-find niche brands.
These consumers are the bright spot in the $2.9 billion high-end-fragrance industry, whose sales declined slightly in 2007. Niche perfumes were only 9% of that market, but their sales have risen 60% since...