Mmmm, I'd have to say my bellybutton, definitely, although it's really frustrating because I can't do anything with it myself. Touching doesn't do anything for me. I've gotta have someone licking and kissing it. Like alwaysmiranda said, I think it does have something to do with it being so close to an even more sensitive area yet not being quite there.
my husband's spot is his nipples or along down his ribcage, that drives him wild...mine would be my high inner thigh...to me that is such a sensual place...
The inner thighs! And if a man has a soft beard...OH MY GOD! Also, my nipples. Stimulating them while being kissed is just oh so erotic. Is it getting warm in here???
My favorite spot...is that soft, thin, sensitive skin in between each finger. Hmmmm, just feeling a tongue sliding very slowly right there is sheer heaven.