ThemeForest - Calpyso - Responsive HTML Error Page - RIP | 183 KB
Calpyso is Error page which will fit excellent for all type of websites, cause it includes flying background items (more flash in your website), and also fixed changeable background image, which is replaceable as you want.
DEMO:
http://themeforest.net/item/calpyso-responsive-html-error-page/3537714