The Traveler's Lunchbox - Project Vanilla: "There are probably easier ways to do it, where you just use a set ratio of beans to alcohol and let it sit until ready. The beauty of this method, however, is that a) aside from the very beginning, you're only sticking used beans in there (which feels delightfully frugal), b) your extract will continue to improve as you keep adding new beans, and c) once you get the ball rolling, as long as you keep using vanilla beans in your kitchen you'll have an unending supply of extract on hand too. Pretty nifty, no?"
Making your own vanilla extract appeals to me tremendously. I must do this.