The only problem I have with cakes that look cool is that a lot of people use that really shitty fondant to give them a design that stands out. Stuff tastes like ass and it ruins the whole cake.
When my brother got married a few years ago, one of his gifts from his family was his "groom's cake." The design was awesome. He is a huge Tennessee Volunteers fan, so they made a cake that was designed like the Vol's stadium. Everyone was excited to try a piece, but nobody finished it because the fondant gave it this horrible taste. Here was a pic of it:
