I used in the past 10mm (or 8mm I don't remember) PP line (the yellow stuff which is usually used as safety line). It is very light (swims on water), nice to your hands, does not kink and cheap. Drawback is that it starts to fluff after some time.
At the moment I use Liros magic sheet (9mm). Not as light and a bit more expensive but free of fluff.

Cheers,

Klaus