Categories of Digital Payment Schemes

Secure Credit Card transactions

examples: S-HTTP, SSL, First Virtual, CyberCash, Secure Courier
short-term solutions (CC's fundamentally costly, inefficient, insecure)
decreased personal privacy

Credit/Debit Systems

examples: NetCheques, NetBill, smartcards
auditability can be desirable
utility depends on conversion to/from "real" currency

Electronic Currency

examples: ecash (Digicash), NetCash
can be made "untraceable" just like paper cash (increased privacy)
can be implemented in software or hardware
might not have corresponance to "real" currency

Prediction: we will see many of each type (no one dominant system)