The bloggers over at cloud-storage service SpiderOak have posted an awesome image depicting a tug-of-war contest between the Ubuntu mascots (plus the SUSE Gecko) and the various cats representing Mac O.S. releases.
Note: The original image is 1920*699 pixels and a layered tiff version is also available for download.
Update: A new set of high def/dual screen wallpaper mods of this image has become available at the link below.
File share for the Linux VS. OSX Animal tug of war Desktop Backgrounds *Set is bundled in a zip file.