Now that Sony has been shut down and cant' even use their own computers to make payroll can other computer systems also be made useless as well. How can our economy survive this kind of problem when it starts spreading? I discovered that the cashiers at Walmart don't know how to make change without the display on the cash register. My bank teller can't explain the difference between a debit and a credit to my checking account. The front office person at my dentist office does not know what a credit adjustment does to my account balance but knows how to make entries in the office computer program. The cashier at the local convenience store refused to take a dollar coin as payment. I then asked her to break a 100 dollar bill. She asked my what bills I would like. I said 10 ten dollar bills, 2 twenties, 2 fives and 10 ones and she gave me exactly that. I had to give her back everything except for the tens. What's going to happen if computer systems start failing?