I know, there are gazillion webpages offering ‘free wallpapers‘. Well, most of the times you end up running a tool like Spybot to remove the crap from your hard disk after a short visit. After you killed roughly half a gazillion gambling, life insurance, porn or pharmacy popups, that is.
Anyway, there is a sweet collection of high-resolution wallpapers over at InterfaceLIFT. Most of them come in widescreen versions as well, no pop-ups, no registration, no hassles. Enjoy!