I saw a nice image, actually this one:

But i felt that it was missing something (and actually it's smaller then the required 800x480), so i started to "kid with it" in Photoshop and actually the final result isn't bad at all :p

Here there are some of those "results", all made by me:








ZIP containing all the images shown above and the original one:
http://dl.dropbox.com/u/1536586/NokiaN900Wallpapers/promotional/nokia-n900.comWallpapers.zip