Deficit Spending
  
Literally, spending more money than you make.
We've all been there, but governments tend to be the biggest culprits. Some economists (cough, John Maynard Keynes) have believed that deficit spending is actually a good thing that can stimulate the economy. We wouldn't recommend it for your own bank account, though.
Example: The Kingdom of Zamunda took in $3 million in revenues from bonds, but spent $4 million on rose petals for Prince Akeem's wedding, creating a deficit. Womp womp.