I racked my brain thinking of something to spend a ton of money on that would be totally useless. Then it occurred to me that when I worked in a gift gallery, we used to sell some of the most expensive crystal in the world.
We had a gentlemen from Russia who wanted to buy over 200 sets of a grouping of grapes that cost 350 dollars each to make a giant chandelier for his yacht. By the time we finished the design in crystal, the COST, Not the retail was up to 350,000 dollars. It was amazing how much he was willing to spend when At the time I was having trouble making rent. (He later flew to the factory and bought the entire lot from the owner of the factory)
So I decided I'd commission a room made of crystal encased columns, crystal encased floors, crystal lit ceilings
I added the girl with a crystal filled hat in a crystal backed frame for the opulence factor.
Please see SBS for my sources (5 years and 2073 days ago)