I didn't want to hijack Gun_Crank's thread, so I'll post these videos here.  It's probably not as cool to full time machinists that see this work every day, but that ain't me and I think these are simply excellent.  These are professionally produced videos from Glacern Machine Tools.  I also recommend their series on milling machines.  There are 13 videos in all, and I learned something from every one.

http://www.youtube.com/watch?v=3SUQKGu7F5w&feature=channel

http://www.youtube.com/watch?v=lcGHtI9Lql4&feature=channel

http://www.youtube.com/watch?v=MwgobIVj4fU&feature=channel

My dog learned to beg by watching me in the bedroom.

Not to mention, been there, done that.

I was fascinated by manipulating the local surface tangency normal to the cutter centerline; the wheels were turning (in my head!), making me think we need to be more aggressive about the design and manufacture of some of our parts.  There will be a battle with the manufacturing guys about the cost of programming for small runs of parts, but I'm thinking they need to be educated and open their minds a little.  Most of our work is not terribly precise except at the interfaces with other parts, and even then we have no better than +/- 0.010 inches on large machined parts.  Mechanisms get more precise treatment, but they are fabricated by specialist vendors anyway.

Back in the 80's I envisioned using a destructive plating process in which the mandrel is consumed while being replaced with metal.  In this way large one piece assemblies of "bones" could be fabricated.  I won't tell you the material for the mandrels because you'll laugh and post the smiley.  Maybe a couple of others, too.  Anyway, in this video we see the start for a different process.