Colored Pencil is a great medium to work in without making a mess. It's my preferred method for rough sketches for an illustration and it's also the quickest "no mess" way to finish the detail in an airbrush illustration. There are a few good brands on the market and quality really matters, especially the whites, or any color when working in reverse. The wax to pigment mixture varies by brand. I generally use Derwent or Prismacolor and work on a smooth bristol plate, but the black surface drawing of the girl and dog below, are simply on construction paper. Staedtler is a good choice for watercolor pencil.

Colored pencil is also used on other mediums of art, such as airbrush illustration and mixed media, to finish out the detail.