The photocard demo applet, included at samples/classic_applets/PhotoCard, is an example of an application that takes advantage of the large address space capabilities.
The photocard applet performs a very simple task: it stores pictures inside the smart card and retrieves them by using a Java Card RMI interface, see Programming to the Java Card RMI Client-Side API. For more information on the photocard demo applet and how to run it, see PhotoCard Sample. The source code is located in the source code bundle at:
JC_CLASSIC_HOME\samples\classic_applets\PhotoCard\applet\src\com\sun\jcclassic\samples\photocard
The collection of arrays (more than two arrays would be required in this case) can easily hold far more than 64KB of data. Storing this amount of information should not be a problem, provided that enough mutable persistent memory is configured in the RE.