I found this, made by the luthier Jens, at Ritter. They usually make great stuff, but this is just a bit extreme:

Inlay in 24 carot gold, and black diamonds, set in platnum of course
bridge, tunners and knobs hand made of gold
3 carot diamonds on top of the knobs
tiny green diamonds on the knobs
body handshapped of a single piece of highly figured maple
nut made of 10,000 year old mamoth ivory

And, it looks as if the neck has been goldplated. pictures here [link] [link]

oh, did I mention that it is priced at 100,000$?