D&D 4.0 Future (4e Sourcebook)/Chapter 5: Equipment/Cybernetics/Cybernetic Enhancements (Rules)/Identity Chip
From D&D Wiki
 Identity Chip
Identity chips provide identification without requiring visual recognition— high-tech ID cards that function even when the wearer is unrecognizable.
Benefit: An identity chip functions as both legal ID and a credit card. The recipient can pay for things even when separated from his funds.
Price: 50 credits