Behold! The Majesty of Space Core! *MILD PORTAL 2 SPOILERS*
I adore this wallpaper. It matches my equally spoilerific Firefox persona featuring Wheatley. :P
But there's no sense crying over every mistake, you just keep on trying til you run out of Cake.
May switch to this, but i'm not sure:
http://browse.deviantart.com/?qh=§ion=&q=Half+Life+Logo#/d1g0skr
http://zeptozephyr.deviantart.com/art/Aperture-Desktop-85562973
This. Which is probably one of the most awesome Computer Backgrounds I have ever had. ^^