Ouch I learned an expensive lesson this month. I'm trying to learn aws and have benefits playing with its systems to the tune of $30/month. I somehow ended up starting two very high cost sessions and saw the first and shut it down the same day. The second, which is similar to the one i started bit on another location/zone I don't recall was not stopped and ran up. $750+ bill. I'm sewing right now if amazon can give me a pass or something on the bill,but this is really unexpected.