Chuck E. Card

The Chuck E. Card was a key card (similar to a credit/gift card) that was used to store save information from Chuck E. Cheese's games that often aren't possible to play in one sitting. The first Chuck E. Cards came out in 1991 with a revision of TechEruo Racing 1000.

Info
An average Chuck E. Card costed around $9.99 at launch (but became around $14.99 by the end due to inflation), and carried 100 save blocks (1 save block can hold 16 KB of SRAM).