Team 2359 created a winch mechanism for our shooter that consists primarily of 3D Printed parts. The only pieces not printed are the lead screw and lead screw nut, some bearings and other misc. hardware. There are 6 parts.
Green Motor Mount and Green Tensioner. Blue take up pulley. Green Ratchet Hub, Red Hub Mount and the Blue Pawls (2 of these one not visible) that hold the ratchet hub in place.
A video of the winch in action is here:
http://www.youtube.com/watch?v=yDsW9tcMrRo
We think it sounds like an old wooden roller coaster.
I hope to have the parts posted on thingiverse later.
***edit*** they are now posted:
http://www.thingiverse.com/thing:271463
Too often teams forget that pretty isn't always good. - Al Skierkiewicz [more] 
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