Green was getting boring, so I switched to blue. Blue made me think of bubbles. Thus, a new wallpaper is born. =P
This theme goes well with blue Tango icons and blue Rezlooks window controls and borders.
Provided is an SVG of the wallpaper, with the Ubuntu logo, and a generic PNG. If you'd like to modify the SVG, go right ahead (use Inkscape).
All work was done in Inkscape. Ubuntu logo Trademark of Canonical Ltd., used under their guidelines for wallpapers.