Guess I am low-tech, but for anything not involving suspending weight, I like strips of torn-up old cotton bedsheets. Run them through the washing machine with fabric softener. They are so soft, yet very strong and inescapable, yet they cut like butter with a knife or scissors if placed under a little bit of tension. Cheaper than rope so you don’t have to feel bad about single use. Also, you can have them in all kinds of pretty/sexy colors: blue, purple, red, rose, pink, black, etc. Even in suspension, cloth strips are nice for tying the wrists and ankles when not part of the weight-bearing rig.