What Do You Use for Robot Casings?

Hey everyone,

What do you guys use for casings around robots, both humanoid and smaller, line following robots?

I saw this article on TechCrunch about a full color 3D printer: XYZPrinting announces a $3,000 full-color 3D printer | TechCrunch

What do you think? Have any of you guys used 3D printing for robot casings? Any other uses you see for this machine?