Crytek's Crysis is a series known for pushing the graphical envelope, but Crysis 3 player K putt's experiments bring the game into 8K resoltuion, where screenshots begin to look more like watercolor paintings than in-game images.
According to K putt's Reddit post, the modder would play the game, find an attractive landscape and up the resolution with keybindings. To change resolutions, K putt used MaLDO's OnTheFly tool, which allows Crysis 3 players to toggle HUD elements and resolution at will. At its maximum resolution, K putt wrote that Crysis 3 ran at 2-3 frames per second.
Check out K putt's Crysis 3 Flickr gallery to see the images at their full 8000 x 3333 resolution, or about 26 million pixels each. For comparison, a 1920 X 1080 image contains approximately 2 million pixels. You can learn more about Crysis 3 in Polygon's review.