Damien Hirst, the bad boy of British art, made this $99 million diamond-studded human skull (ok, ok, not real skull - it's a cast of a skull):
"For the Love of God" is a life-size cast of a human skull in platinum and covered by 8,601 pave-set diamonds weighing 1,106.18 carats. The single large diamond in the middle of the forehead is reportedly worth $4.2 million alone. Hirst financed the project himself, and estimates it cost between 10 and 15 million. Of course, it will cost someone a pretty penny to own the work: It's priced at $99 million.
Link - Thanks Tiffany!