From exoskeletoncabaret's caption:
Liz and Austin's steampunked wedding cake. The metallic gears, doors, rivets, and panels were all made of fondant and were entirely edible. This is probably the baddest-ass wedding cake you will ever see. Respect. Best part: the cake tasted just as decadent as it looked! I had a slice of the lemon layer after photographing it.
Check out another shot of this amazing steampunk cake over here.