"Nanobot" by Caroline O. Berg

This nanobot serves a very specific purpose.  This travels through the bloodstream and destroys unwanted clots.  It is currently depicted with its scythe-like claws out, but they are retractable.  Normally, when it is just traveling around, it is smooth as a bullet, with no sinister blades visible.  Here, it is about to preform minor surgery on another unsuspecting clot.  As for the green blood - it is obvious that these nanobots are traveling through an alien bloodstream.

Created for my concept art class.  We had to create 75 different robots.  This is one of mine.  Originally I didn't have blood, but then I realized that blood would perfectly complete the image - it gave the nanobot purpose, as well as gave a size reference.

Drawn in pencil, then colored with Photoshop and GiMP.