I don't have a picture of it, but it's been awhile since I saw a tool that I must have. Today I saw one. A sledgehammer with a solid copper head. Not really useful for the average person, but you can whale on a 4" diameter pin without mushrooming the head like you would with a regular sledgehammer, nor do you have to hold a block of wood in between to avoid said mushrooming. Just beat on the pin like a red-headed stepchild.
It's a gigantic version of a little brass tapping hammer. The owner said it was about $500. Think I'll price shop a little.