Java Card: The unsung hero of the Java Platforms
By dannycoward on Mar 20, 2009
There's an excellent technical overview of Java Card here.
Java Card is deployed all over the place: from SIM cards, to cash cards, to security badges and national identity cards.
Those of you think that Java Card is too small to be interesting may be surprised to hear that smart cards, like most everything else, are growing powerful enough to run a mini-web server. The latest latest version 3.0 of JavaCard includes support Java Servlets (2.4) (in which the Janitor had some part to play). That's in addition to the existing applet based model.
There's quite a number of practical looking Java Card sessions in store for JavaOne this year.