What is this Dead End Thrills thingy? Artistic videogame fauxtography?
Yep. Some people rant its pretentiousness, but he really has
produced some beautiful shots (I don't care if they're pretentious or not, really). With each screengrab he usually describes the game it was taken from and/or the various hacks and mods he used to get the shot (either that or he relays some witticism or short life story). A few of his posts are promotional or concept art (some of which seems previously unreleased) but most of it's screenshots.
All of the non-community-contributed stuff is also always available in a wallpaper format (usually 1920x1080) and much of it is also available in huge print-friendly resolution, so you could make yourself a quite-nice-looking poster if you have access to a print shop. The user-submitted stuff just has to fill the width of the page (1024 pixels) but it doesn't necessarily have a larger resolution available, and if it does it's not necessarily 1080p.