This is a thought experiment: My PC is mounted on my ceiling. I want to run a USB peripheral through a cylindrical retraction device (like a dog leash). The device is going to mount to the ceiling also and rotate about it's vertical axis. This will allow me to pull down the mouse from the ceiling and use it at any point in the 10x10ft room below. NOW, let's say I want to be able to rotate around that retraction device with impunity, as many times (in one direction or the other) as I want. The problem is this: as the USB cable is pulled around and around it will begin to twist and eventually fail. I thought that a possible solution might be to let the USB rotate (to prevent the twisting) at it's connection point on the PC, but this device doesn't seem to exist. Also, what about proprietary (non-USB) cables? I have a real use case, but it's too hard to explain.