The Furlong/Firkin/Fortnight measurement system

The Furlong/Firkin/Fortnight (FFF) system is a humorous system of units based on outdated or impractical measurements. The length unit of the system is the furlong, the mass unit is the mass of a firkin of water, and the time unit is the fortnight. Like the SI or metre-kilogram-second system, there are derived units for velocity etc.