An experiment for the Discovery Channel show Mythbusters went awry earlier this week, leaving two families with massive holes in their homes.  Mythbusters hosts Jamie Hyneman and Adam Savage were trying to prove how effective a cannon would be at firing non-cannonball objects. First they wanted to test an actual cannonball, and shot one off towards a nearby empty hill. But something went wrong, and the cannon overshot the hill into the town of Dublin, CA, where it crashed into two houses before coming to a stop inside a minivan.  

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