My son had another birthday today and I made him this Bug Mountain Cake. I modeled it after the Dino Birthday cake, of yore. Actually, the idea in the first place, originally from the Family Fun website (called something weird now) was a Bug Mountain.
He loved it and so did his friends. Check out the Dino Mountain post (linked above) for directions (and a cake recipe link, frosting recipe, and how to make the "dirt"). For the bugs, we just used sugar bugs I bought online. They are totally edible!