I just finished this vest from an old, old pattern. It uses two threads, each on an alternate row. By working on a circular needles, you just knit one row/one thread, then go back to the beginning and repeat with the other thread. It made the Boucle' go further and really features it. The other yarn was a plain navy one.
It was fun to knit-I like unusual ways of doing things. The closure is a hair ornament the just slides out of my hair, so it's nice to find a use for it. I bought it at a Craft Fair. The model is my dress form.