It reminds my good days programming simcards, i was the founded of a startup in Brazil that made a good use of simcard programming to store two numbers in the same simcard, around 2010 it's a cool and profitable, the thing is that i managed to insert a local imsi and an a north american imsi registered in the same card so everyone that travel abroad could be free of expensive roaming charges, them we sold the company and now days they are a reseller for some major carrier in US =)