Wink [Q]Saving sim cards, dual sims and the link between autonomous sim cards sharing IMEI

What exactly is preventing my phone, from saving say an "image" of my sim card, and using it while the sim card is not technically physically in the phone.

Is the S4 capable of utilizing a dual sim scenario? And if so on what rom would this be possible, if it is even a rom dependent function.

Finally, obviously on the end of cooperating service providers, it would be a simple task to see the same IMEI connecting to both networks at different times. Is this something that is possible to conceal on my end, from those service providing bodies?

Thanks for any input you have, and don't get totally hung up on the S4 aspect of this, consider the questions preceding, and succeeding the possibility of the S4 to take part in this function.