Had U.S. Bank do that to me when I was a high-schooler on my first job. Time stamps on the transactions came in pending - next morning I had 2 overdrafts and fees to go with them. Cleared that account out the next day after getting them to waive the fees.

$35 usually. Then a $5-$10 per day for each day it is over drafted. Usually it caps out at a certain amount. Now a days a lot of banks let you use your savings, or credit card with them as a backup for no charge.