Do they send you to jail? what happens?
      Answer1:I didnt pay mine for a while. They prevent you from both bidding on and posting items. Thats about it as far as I can tell. Ultimately they will cancel your account, but you will be able to open it up again if you pay what you owe.Regardless, dont worry about it. Just do not plan on using that account again any time soon.
      Answer2:They put a freeze on your account, if you have a paypal account or a debit or credit card on file they will take it from you automatically.