The DesktopGaming site homepage randomly selects one for it's huge banner, and there's an updates and popular section at the bottom. But I suggest clicking on 'browse' at the top and finding your own. The site lets you browse by 12 different systems (including some handhelds, PC, and even Arcade game desktops too), upload your own game desktops, and even teaches you how to best make them using emulators. Give it a good looking, you might find one you really love.
[*].disqus.comto your security software's whitelist.