Gary Sterley, a graphic designer, used a 3D printer to create an iconic piece for a true-to-game costume based on the Crimson Fist Space Marines from Warhammer 40K. The fully articulated crimson Power Fist was printed using Sterley's Solidoodle2 3D printer and is the most noticeable piece of the total 7-foot-tall costume. He documented the entire creation process from conception to printing to final paint and assembly, including step-by-step instructional videos. Check out the more details in this article: http://3dprint.com/19385/3d-printed-warhammer-cosplay/

Below is a work-in-progress picture of the large-scale Crimson Fist: