Bought at Walmart: one polyester circle scarf, on clearance for four dollars. The quality of the scarf is not amazing, and the edges aren't finished in any way; it's just a sliced-off piece of fabric with a seam up one side. I bought it because it's one of my most favourite colours in the world, and because when it's on and scrunched up, you don't really see the edges.
(Scrunched up as if you were wearing it)
What I did: added one pair of snaps, inside the seam and directly opposite.
Now it can also be a poncho or cape. (You snap it together, making two "neckholes," and the second one goes to the back.)
If you have an underused circle scarf, or a tube of knit fabric, and a snap, you can make one too!
UPDATE: I added one more snap (not a pair, just one half) at the other end of the scarf, so that it can also be worn cocoon-cardi style.