NASA' Jet Propulsion Labs put together a wonderful flash-based presentation to bring you up to speed near-earth objects (NEOs), asteroids, comets. meteors and potentially hazardous objects.

If you have DSL, there is an Flash version of the presentation.

If you are on dial-up, there is an HTML version of the presentation as well.

Courtesy of PBS.Org, WGBH Eucational Foundation,
NOVA scienceNOW, and Paul Chodas-NASA/Jet Propulsion Laboratory