At Mardi Gras in New Orleans there are special bead necklaces which can be used for a lot of things, e.g. picture frames ;-)
I’ve seen such necklaces here, too, mostly on flea markets.
Links:
Mardi Gras Bead Frame (Mardi Gras Bead Craft: DIY Monogram Letter)
=> scroll down to: ‘Tutorial for a beaded photo frame’