Check THIS out...

Google Mars.

I thought it was cool to find Area 51 on Google Maps...the sci-fi buff (and writer) in me is going apeshit over being able to take a tour of Mars...

The map of mars featured on Google is composed of images taken from the Nasa JPL lab.

Check it out, but be forewarned: you might end up killing an awful lot of time just browsing the surface of an alien world.