An old picture frame, a piece of pegboard picked up on the side of the road, some paint, thin black elastic, and an hour or so of threading and re-threading. Neat and tidy.
I used 2 types of elastic: narrow flat elastic and shirring elastic, because that's what I had. I might do another layer going in the opposite direction, too. If you have enough elastic, some sort of intricate cross-stitch design would look nice.