Be sure to have conky-all installed, and comb through these for hard coded paths that you'll certainly want to update to match your setup.
I wanted to see details on the moon
The current phase is simply calculated with a python script, while the latest image is pulled from US Navy
With a bit of scripting, the latest image can be automatically set as wallpaper upon updating. Includes cron file for updating the image.
Similar to the moon config, but of earth
Earth, however, has more going on that the moon so I've added global news RSS feeds as well as the top 5 most popular pages on Wikipedia in an attempt to see what currently has people interested globally.
Radar is specific to Austin, TX, but shouldn't be too difficult to modify for your own area.
The sun with associated facts and regularly updating images from various Sun satellites.
Mars with associated facts and a few images from its various satellites.
I have yet to automate pulling the latest satellite images. NASA makes this difficult.
Saturn with associated facts and images of north pole, south pole, and a map of moon orbits.