Look out below!

Are you worried about an asteroid hitting the Earth? NO? Good grief, why not?!

NASA is tracking asteroids and has a web page showing 943 near-Earth objects. Scroll down to choose one and wait for the Java applet to download. Then you can set the system in motion with the button that looks like this >> (fast forward), you can zoom and scroll in 3D — why, you can get lost in space.

Here's the article in the Wall Street Journal that told me about this.