I had no idea about this...
You can purchase these straight from the US Treasury department, sheets of actual printed bills that can be hung up on the wall... or even cut into bills and used as currency if you wanted to for some reason! (Joke, shock value, etc.)
A sheet of 32 one dollar bills is only $61 bucks! 16 $50 bills is $900 bucks though... totally worth it for something like walking into a government office or something to pay a bill or debt, and asking to borrow a pair of scissors to cut out the money in front of them to pay your bill... O_O