Wouldn't you like to have a $60,000 shower in your house? We can have it if we want it; it's ours for the taking.
My youngest brother works for a company that manufactures carbon fiber products. If you don't know what carbon fiber is, check here. If a carbon fiber board doesn't meet specifications, it can't be used. Each board (depending on size) has a retail price of around $10,000.
We've got six reject boards sitting in my dad's workshop. One of my family members had the "brilliant" idea of surrounding the walls of the steel shower in our basement with these carbon fiber boards: no rust, and wow, is it indestructible!
I still don't think we'll go this direction. Bookshelves, maybe; shower? No thanks.