This wallpaper isnt gnome specific but its my first wallpaper release for the linux community. It's based on a vector version of the modern GNU logo I converted. The original pixmap version is here http://www.gnu.org/graphics/gnu-alternative.html
The vector was done in Inkscape and the background was done in GIMP.
The original image was 2mb so I had to index the colors so that the file size can decrease. Comments welcome.
The background is under Creative Commons: Attribution-NonCommercial-NoDerivs 2.0 and the vector gnu logo is under GPL. If you want to obtain a copy of the vector email me.