The universally accepted currency, at least in the Red Dwarf universe. One-hundredth of a dollar-pound is a cent-penny. As those names imply, it's a combination of dollars and pounds. This is one reason you sometimes hear Lister or Rimmer refer to using both dollars and/or pounds in the TV show. It's not that the show's creators couldn't remember if they were American or British, because it was a sort of combination of both. I remember when watching one episode I got confused when Lister said of himself, "This arm is as sound as a dollar-pound." I'd never heard of a dollar-pound. When I finally read Infinity Welcomes Careful Drivers, I learned that was the standard currency used throughout our solar system. It's been a while since reading the book, but I believe the slang for dollar-pounds was buck-quid.

Neither the TV show nor the book mention why dollar-pounds exist, so unfortunately, I can't provide you with any history on where they came from, or the government/banks backing them, or anything in that regard. Please feel free to use your imagination.