A substitution for currency, used by some big businesses during the 1800s
Many wage-laborers didn't have cash on hand. To promote the intra-company economy, businesses would offer notes called scrip that only had value at company-run businesses.
Scrip was used in big businesses to make their workers buy from their company stores and keep them in debt. This limited workers being able to jump from job to job because their money would then become worthless.
Think of it as "Monopoly money" in several ways: it's as worthless to real banks as Monopoly money is, and it was used by monopolies to keep the little guy down! --Thanks to Alex