Years ago I discovered a knot which I call the “Knotangler” (i.e., “No Tangler”) because it’s a knot that lets you bundle up any kind of line (computer cables, speaker wires, extension cords, headphone wires, charging cables, ropes, etc.), either for storage or to just shorten the line, as needed with many electronic cables, all in a way that they can be undone without getting the line in tangles. The instructions for making this can be obtained at:
Use coupon code KNOTTY to get the pdf for free.
One Idea 