@SYS_V: in fact many SIMs do contain a microprocessor for extra functionality (see SIM Application Toolkit)

IIRC there was a talk at CCC about putting your own apps into SIMs using special SMS commands

@IgorSkochinsky I corrected the post. I found this: blog.ptsecurity.com/2014/12/…

"Then we may easily issue commands to well-known TARs and manage them; e.g. Card Manager allows installing a Java application to the SIM."

2014.phdays.com/program/tech/36814

slideshare.net/phdays/…

apparently "SIM cards are fully programmable computer systems"

but im guessing you knew that already...