I've decided to go with a nuclear theme in this thread. Below, you will be able to see how far the radius of a nuke on, for example, Columbus, OH would reach. There are multiple bomb types to choose from, including one of the largest ever, Tsar Bomba.
http://www.carloslabs.com/node/16
Below, is a video on the explosion of Tsar Bomba. Be sure to read the full description of the blast on the right for details regarding it's creation and strength, etc. Imagine all of Cbus burned clean off the map is seconds. I mean fucking clean. I mean really think about it. Go ahead. Do it. I'll wait. Watch the vid while you're at it.
http://www.youtube.com/watch?v=LxD44HO8dNQ&feature=related
Holy shit! Right? That's just an amazing amount of power. Even the Hiroshima bomb is like a firecracker compared to, well, a huge bomb.
And, I'll close this up with recommendation for an older movie that I know many people have never seen.
"Miracle Mile"
It's a suprisingly good movie about a guy who accidentally finds out we're about to engage in a nuclear war and it's a countdown to the end. I don't want to say anymore and ruin it for those who may wish to see it, still. I don't believe you'll be disappointed.