The universe technicians looked at the pedestrian's reality.
   "Something went wrong with this one."
    "Oh?"
    "Do you see the water gushing out of the gutter and tumbling into the
   sky?  The poor pedestrian hanging onto the ground for dear life?"
    "Seriously?  This isn't another practical joke?"
   A nervous [1]amazon.com avatar ran fervently into the technician room.
   "YOU HAVE TO BUY MORE -- sorry"
    The amazon avatar changed into a sewer surfer.
   "Hi I can fix this.  Gravity turned upside down in our universe.  All
   you have to do is spin the world so that gravity is going down again."
    "How did you get out here?"
    The sewer surfer gestured at the universe as if it was obvious.  "This
   is an emergency!"

References

   1. http://amazon.com/