People do dumb things for their 15 minutes of fame, and this guy attempted to be one of those people. He wanted to take the Mentos/Coke thing to the next level, obviously at the risk of his own life.

As you can see from the results, the outcome, well...  Don't repeat the experiment, as you'll be wasting a lot of perfectly good Mentos and Coke.  Besides, it's already been done before.