This is something I sort of invented. I posted the idea in this thread on hammock forums, and received a great response. Previous versions have been made by Redolearly and John Sawyer. However, my approach does have some advantages.
This version doubles as a regular stuff suck and ridgeline sack, but does not require any extra clips or carbiners. It is also the lightest version I have seen weighing in at 13 grams.
The construction requires a couple of strips of grosgain attached to some mitten hooks. All of the materials can be purchased from Quest Outfitters.