"The Nikon D5100 offers not only in-camera RAW file processing, but also provides Nikon's extensive in-camera image retouching capabilities. These include resizing, cropping, post-capture D-Lighting, redeye correction, monochrome and other filter effects, color balance, image overlay, quick retouch, straighten, distortion control, perspective control, miniature effect, fisheye, color outline, color sketch, and selective color."
A handful of Nikon cameras allow the user to use the *camera* to post-process images, and make as many different JPEG variations as they would like. Handy if you do not have a computer at hand, or just want to kill some time, or to just use the camera to help you make different "looks" to images. Canon is starting to do this as well, some seven years later...
"The Nikon D5100 has six presets called Standard, Neutral, Vivid, Monochrome, Portrait, and Landscape, and up to nine custom presets can be defined, named, saved, and copied. Sharpness can be adjusted in ten steps, along with an Auto setting; contrast, saturation, and hue can be adjusted in seven steps, while hue is adjustable in three steps. There is also a five-step "Quick Adjust" setting, which exaggerates or mutes the effect without having to adjust each slider individually. When Monochrome Picture Control is selected, Hue and Saturation are replaced by Filter Effects and Toning respectively. Filter Effects offers Off, Yellow, Orange, Red, and Green settings, while Toning offers B&W, Sepia, Cyanotype, Red, Yellow, Green, Blue Green, Blue, Purple Blue and Red Purple settings. Note that Picture Controls are only active in Program, Aperture-priority or Shutter-priority and Manual exposure modes, as the Scene modes already apply preset image adjustments. Of course, the Nikon D5100 also offers sRGB and Adobe RGB settings, in a separate Color Space menu."
from imaging resource's review of the Nikon D5100 .http://www.imaging-resource.com/PRODS/D5100/D5100A.HTM