We've had this system in the uk for a few years now and it's excellent. You can set up an overdraft amount with the bank. If it's nil, all transactions that would send you overdrawn would not be paid. Payments that take you below zero but within the agreed amount cost interest of 40% (so it would cost 400pounds to borrow 1000 for a year). That's a steep rate of interest, but there are no fees. If i borrow 1000 pounds for a day, the cost is 1pounds10p. I can take 100 pounds out 10 times in a day, pay it all back the next day, 1.10 in interest. I've no argument with that!