I have always been fascinated by nuclear weapons so I found this app very interesting. It uses an interactive Google map and allows you to virtually nuke any location in the world with a nuclear bomb of your choice. It calculates statistics on the blast radius, radiation and fallout radius and casualty rate. Very, very interesting.
An interesting article that expresses what I have felt for a long time to be the best way to learn and improve in anything. In short: Practice makes perfect. Produce a large quantity, and the quality will follow.