Litter box cake

I was surfing, trying to find some fun Halloween ideas, and came upon a recipe for Litter Box Cake.  My sister and I made this for my Mom's birthday a few years ago, and it was hilarious, although my Dad didn't appreciate it!  We didn't follow a recipe, but ours looked very similar to this... Kitty Litter Cake.  Warning- this cake will make some people gag- though it is delicious.