Drag Chain Mounting Bracket
One of the first things I made with my printer was a drag chain
http://www.thingiverse.com/thing:815736
Finding a way to mount it was fruitless and I got buy with wire and zip ties ... till I made this part.
This thing is modeled after the common end-switch holders, and clips onto the bottom of an 8mm Z-axis support rod. It's just skinny enough to fit between the rod and the aluminum Z motor coupler
Unfortunately the hot end of the drag chain depends on the extruder mount, which seems to vary quite a bit so you're on your own there!.