The only other screen background I have seen is from the person who initially requested this feature, and her design is not released yet.
There are two places that I know of to upload DC stuff:
The Magic Mirror
http://frua.dns2go.com , which contains both FRUA and DC files. There is an art folder for DC but I don't think it has a specific one for screen backgrounds. Perhaps the Misc folder will do. Mention in your descriptive file that it is DC related.
Ziroc has an art archive, and has a section for Global art such as this. I'm not sure if he allows direct uploads but if not you can probably send him the file.