GeForce owners can now take pro-grade 2D, 360° and Virtual Reality 360° screenshots, courtesy of NVIDIA's Ansel technology. All you need to get going is a 600 series card or newer, the latest drivers, and a copy of Mirror's Edge: Catalyst, the first game to support it.
Just hit Alt-F2 in-game to access Ansel, at which point you can capture freecam screens, change the field of view and rotation, throw in filters, adjust contrast and brightness, and more; if you use Android and Cardboard, you can download the NVIDIA VR Viewer to check out or upload your handiwork in 3D; lastly, head this way if you're a VR user for instructions on getting started with that.