Does anyone know how to knit this ribbon scarf?

That one is fairly simple to knit, on size 8 or 9 needles, cast on 40 stitches. Work the first and last 10 stitches in garter stitch, and the center 20 in stockinette until the scarf is as long as you want it. On the last row, knit the first 10 stitches and move them to a holder. Bind off the center 20 stitches, ending your ribbon at the 20th of these stitches leaving several inches for a tail (pull the last stitch knit straight up and out after you clip the ribbon) and simply slip the last 10 off the needle and unravel them down to the bottom. Take the first 10 stitches off the holder and unravel them to the bottom. You may adjust the number of stitches either in the center or on the edges as desired.

It sounds like you may be talking about the magic scarf pattern

http://www.knitlist.com/95gift/magic.htm

or something like Clapotis

http://www.knitty.com/ISSUEfall04/PATTclapotis.htm...