*UPDATE! Butaflor is no longer a registered trademark of Robertet's -- registration expired March 4, 2006. So, butaflor it is!
From Steffan Arctander's Perfume and Flavor Materials of Natural Origin:
"Butaflor is a registered name (P. Robertet & Cie.) given to a series of highly concentrated perfume materials produced by extraction with butane at subnormal temperature. The solvent is recovered by evaporation at room temperature (boiling point of butane is -- 0○.50C.). The low extraction temperature and the selective solvent result pale-colored, almost waxfree and terpeneless product. The method is particularly useful and advantageous when applied to the very delicate or heat-sensitive botanical materials, e.g. lilac flowers, lily of the valley (muguet), orange flower, jasmine, rose, etc. Certain staple materials are also treated in this method, e.g. ginger rhizomes. It should be kept in mind, that not all Butaflors are completely alcohol-soluble."
I'm planning a little butaflor exhibition for the perfume event (in May -- yes, I know, I'm repeating myself). I think I'll go to the florist and grab up a bouquet of stargazer lilies for the experiment, since they have such a gorgeous, deep, sweet, sticky floral essence. Someone suggested I distill something whilst everyone was milling about checking out the fragrant goods, but distillation takes a long time and nobody likes watching water boil, because, y'know, it never does when you're watching it.