This site is better known by it's moniker: Wallpaper Abyss.
This is a site that allows users to upload large (I mean MASSIVE) files for use as free wallpapers. So far, I haven't experienced any "pop ups" like you do with Wallpapergate.com.
This is a far superior site. Submissions are monitored, no nudity or partial nudity is allowed, and users receive points/badges for reaching certain milestones. Points can then be used to by "raffle tickets" for various items each month.
My profile: http://wall.alphacoders.com/profile.php?u=Gun665
If you click the images they go larger and larger until you have an image that could feasibly be wallpaper for your living room.
UPDATE: (12/2011) This site now offers a showcase for photography, artwork, and avatars as well. (Get a cool avatar for free, woo-hoo!)