If you are like me, you probably have too many cards to fit into your wallet.

Credit cards, library cards, bank ATM cards, grocery store loyalty cards, driver's license, prescription drug card, even coffee club cards -- more cards than you can keep track of.

Wouldn't it be great to have a single card for everything?

This article from an Idesco Oy representative paints a vision where one card does it all:

"Until recently access control systems have not been compatible with other systems. In each access control system, tags and cards have to be bought for this sole purpose. What if we could use our personal bank or travel card in accessing our secure work place? Imagine the card being valid for all the purposes; access control, shopping, travelling, different kinds of payments etc. 13,56 MHz technologies brings this dream to reality."

Texas Instruments also is touting the interoperability of 13.56 MHz (medium frequency) systems and embracing the concept of a single solution card:

"Employee badges are moving beyond just access -- to single-card security systems that have to work harder to deliver a host of solutions from time & attendance to authorization to cashless transactions. The technology is ideal for large "campus" settings like corporate office parks, schools, health centers and hospitals, where single-card solutions connect employees, students or patients and staff with a range of networked security, authorization, information and transaction systems."

It sounds like a single-card solution is viable today in controlled environment settings, including self-contained campuses where one entity controls the functions for which the card can be used, and possibly in societies like China where central-planning still has a firm grasp. In North American and European culture, where there are so many free choices for so many different services, I think it will be a long time before we move to a single card solution in our everyday lives.