Hot tip: don't attempt to put out a grease fire with water! A family had a little incident in their kitchen after something on the stove caught fire, and instead of smothering the fire, the dad throws a bucket of water on the flames, causing a small explosion.
Next, sometimes you're just in the wrong place at the wrong time. Two dudes in Brazil were walking down the sidewalk when a huge explosion knocked them into the street. Officials found that a leaking propane tank inside of the restaurant was the cause of the explosion. Thankfully, neither of the guys suffered any serious injuries.