Sounds like double-knit is your best bet -- then (as you suggested earlier) you can have the back be the reverse (negative image) of the front. Unfortunately, if you choose a thinner yarn to compensate for the double-thickness, that'll mean more stitches to knit. (And doubly more if you do double-knit.) Ack. Could you maybe duplicate stitch or embroider dots after the fact? Or hmmm... I don't know what look you're going for, but it might be kind of funky if you made dots out of buttons -- you could have one on each side of the fabric and sew them together, if you know what I mean. (Sort of like little barbells anchored on both sides and connected in the middle -- but secured to the scarf so they wouldn't fall out, of course.) Or maybe there is a way to do that with yarn... I know I've seen instructions for making little button balls out of yarn -- using a crochet needle I think. Sorry for the babbling... just thinking as I type.