This is how one can construct a rather useful cable hanger from some random stuff.
The spring is from an old Hewlett-Packard scanner, where its function was to guide and protect cables running inside it.
The function of the cotton string is to pull the spring against the moulding, so that the edge can better support the spring and the weight of cables. Before wrapping, it may be safest to secure the other end of the spring with some duct tape.
From this kind of a rack it is easy to get a picture of what kind of cables are available with just a quick glance.