Planetary Destruction with a Coffee Can

There's a funny humor piece at http://www.deepastronomy.com/how-to-destroy-earth-with-a-coffee-can.html that talks about destroying the earth with a coffee can.

It's a fun read, but as one who works for an organization that develops various evil technologies including planet destruction devices, I can assure you that while it takes more than a coffee can to destroy the Earth, it takes far less than "107,000,000,000,000 nuclear bombs".

What you really need to destroy the Earth is a destructive force that grows at an exponential rate you can either think along the lines of von Neumann machines or chain reactions.

Believe me, hitting the Earth with adequate force in a single shot is just not going to work.