Andrew Price (Blender Guru): https://www.blenderguru.com/tutorials/rope
Rope: http://darkscarab.com/view/66
This one spins 3 circles around a Bezier:
http://www.reynantemartinez.com/how-to-model-a-rope-in-blender.html
Cylinder - Main Rope
Armature - Main Rope Armature
Curve - Main Rope Curve
To prevent resizing of armature bones from sliding along curve, on the bone constraint, where we select Spline IK, under Chain Scaling, select Y Scale Mode=None, and XZ Scale Mode=None. (Use Curve Radius is checked, but this might not be important.)