We chuckled a bit. Then I took the plunge not expecting to find much by image google searching "plastic bag origami." The results rolled in. Why i'm stunned, i'm not sure.
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Apparently, they mostly reference instructions on how to 'football' fold a plastic grocery bag to take up less space. My thoughts... just use a reusable canvas shopping bag.
"ooooh... mr. cable... why won't you go there. Uhhh.. i'll be right back."
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Here's a more creative use of plastic bag origami... as a wreath. Check out the Craftzine blog for additional recycle / reuse ideas.