Such as gold watches(Will tell time when used; sell to merchants), Golden Teeth (which can be implanted at a doctor for extra dialogue like tatoos), and golden coins (They really should exist in the game, maybe not to replace caps, but to just show the NCR's progress to Fallout 2)
Maybe craftable frag mines, I've yet to see them employed ever, and even 5000 year old Chinese people made land mines, so why can't we?
Bear traps, etc, more craftable stuff pls :3.
Maybe a few NCR Merchants could have Gold Coins in their inventory, worth the same as caps, but to show the wasteland is adopting the currency.