10 Fun Ways to Destroy Planet Earth

Every one of these 10 Ways to Destroy Earth is scientifically plausible, although highly, highly unlikely. This is a doomsday list like no other, and something that should be kept out of the hands of geek terrorists... Example:

Essentially, anything can be destroyed if you hit it hard enough. ANYTHING. The concept is simple: find a really, really big asteroid or planet, accelerate it up to some dazzling speed, and smash it into Earth, preferably head-on but whatever you can manage. The result: an absolutely spectacular collision, resulting hopefully in Earth (and, most likely, our "cue ball" too) being pulverized out of existence