I know…not too original, but I thought that you might enjoy them. The models were created by DaveC at the Indigo forums.
The two with the back lights were rendered with Blender Internal and the one with the logo laying on its side was rendered in Indigo.
Here is the original thread at the Indigo Site. There are some renders of regular Ubuntu logos that turned out pretty nice also. http://www.indigorenderer.com/joomla/forum/viewtopic.php?t=2496
Thanks for looking.