Credits
The following are the pictures used for promoting Spherualizer. I am not the owner of the pictures and I want to thank these creators for sharing their work for free. All these pictures are released under Creative Commons license and you are free to download them from Flickr and add it to your Spherualizer's gallery. Before downloading the pictures you should read and accept the associated CC License.
Special thanks to Bob Dass which is the creator of Picture 8, the default picture displayed after the first installation of Spherualizer.
You can find a lot of awesome equirectangular pictures optimized for Spherualizer on the Flickr's Equirectangular group.