I wanted to announce that about 100 new images have been posted to the Background Image Gallery in the last couple of days. Thanks, Derek!
The gallery images should have public licenses in order to be posted here for download. However, many other images are available online for personal use only, and when downloaded and cropped to the proper height/width ratio as described in the Users Manual they can serve as backgrounds for a really nice, themed organizer. For example, a collection of very high resolution scans of old, rare manuscripts can be found at http://www.lindahall.org/services/digital/index.shtml
for creating what I think would be a very distinctive organizer (my next one, in fact).