http://www.thefirearmblog.com/blog/2018/03/15/rex-silentium-bitcoin-suppressor/
This is an interesting development! You can now buy a silencer with bitcoin, dash, or other cryptocurrencies. Leave it to Montana to be the first, to my knowledge, to adopt crypto for anything in the firearm industry. You still have to fill out all the dumb paperwork to please Uncle, but this is great nonetheless.