This site seems to be very good. You take the quiz with your partner, but in private, and then it compiles all of your answers and shows you only the matches. Matches include fantasies and desires that range from where you want to go for a good time to threesomes and bondage. The downfall: it costs money. For a 3 day unlimited usage its not too bad though (around $13), unlimited use is close to $35 with shipping and all. Guess if your really interested this might be a good purchase. Check out the short sample:

www.fantasyshare.com