I made a bear hanging system like the one sold by BPL. I used a large and small silnylon stuff sack from REI, a small carabiner, a large OP sack, and originally some lightweight nylon cord.
I’ve since bought some of the bear bagging cord from BPL, I highly recommend it since it’s nice and slick and glides over branches well, plus it doesn’t tangle as much as the other nylon line I was using.