Over the last couple of weeks, I've browsed a number of sites looking for a new desktop background.  Yes, I consumed my time with this side project, but in an effort to beautify my Windows experience, I stumbled upon some truly magnificent examples of nature photography that should definitely be shared:
 25 Breathtaking Examples of Nature Photography

Earth Science Picture of the Day

Astronomy Picture of the Day

National Geographic Galleries

The Big Picture

NASA Photojournal and the NASA Archives

More sites to come...