I’ve gathered all of the official Ubuntu wallpapers and posted them here for anyone to download and use as their own. Enjoy!
Ubuntu 4.10 Warty Warthog
Ubuntu 5.04 Hoary Hedgehog
Ubuntu 5.10 Breezy Badger
Ubuntu 6.06 Dapper Drake
Ubuntu 6.10 Edgy Eft
Ubuntu 7.04 Feisty Fawn
Ubuntu 7.10 Gutsy Gibbon
Ubuntu 8.04 Hardy Heron
Ubuntu 8.10 Intrepid Ibex
Ubuntu 9.04 Jaunty Jackalope
Ubuntu 9.10 Karmic Koala
Ubuntu 10.04 Lucid Lynx
Ubuntu 10.10 Maverick Meerkat
Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.2.11) Gecko/20101013 Ubuntu/10.04 (lucid) Firefox/3.6.11
Very Amazing , Ubuntu beauty every day
Mozilla/5.0 (X11; U; Linux i686; en-US) AppleWebKit/534.7 (KHTML, like Gecko) Chrome/7.0.517.41 Safari/534.7
Hardy Heron is by far the best :]. I use that wallpaper on my Ubuntu 10.10
Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.2.12) Gecko/20101027 Linux Mint/10 (Julia) Firefox/3.6.12
The best for me is the hardy heron, I think ubuntu should learn from linux mint about wallpapers haha