I hear that and want to kill myself. Rigging is a process in CG animation in which you take a model and make it move to put it in simple terms. You set up bones, Weight Maps, IK/FK (Inverse/Foreward Kinematics), Endomorphs, etc. What nuclear physics/rocket science is to Science is what Rigging is to animation. It is a very technical process, and some people specialize in that particular field in the industry (and make the most money because no one wants to rig. It's a headache.
But I figure I'd feature something I found pretty pimp while browsing CGTALK.com forums. Mattias Jervill (http://www.jervill.com/) created a pretty awesome rig for a Transformer character. You can view it here, or visit his site for a higher-res version:
Like I said, that's pimp!