I made this cake for my bosses son's 6th birthday. They had a beach theme so I thought this would be perfect. I made a chocolate cake with a caramel buttercream filling and frosting. After a bunch of experimentation I decided that rice crispies can be molded into almost anything and that some graham cracker crumbs mixed with some brown sugar make the perfect substitute for sand. From what I hear it was a great success and I will definitely make it again, even though the caramel was a pain to make and took many tries to get the hang of.