Who is using smart card technology for network security today?

Some four million federal government employees have either a Personal Identity Verification (PIV) Card or a Common Access (CAC) Card.  Both of these have a smart card chip in it that is equipped to provide secure logon, once federal government IT departments ready their systems to use it.  As for the private sector, many blue chip companies including Pfizer, Boeing, Microsoft, Chevron, Caterpillar, P&G, J&J and many others have already implemented some form of smart card-based network security