Ideas, Anyone?

I saw the most interesting scarves today. They were ribbed. But not normal ribbed. They were ribbed so that one side of the scarf (ie. the right side) was one colour and then the other side (ie. the wrong side) was a different colour.

I stared at it for the longest time, but couldn't figure out how it was done! The I stretched the scarf width-wise, the gaps in between the ribbing didn't look as they should. Instead of the little bumps from the purl stitches, there were "V"'s. Weird, huh? I think it is the most amazing ribbing I have ever seen.

Too bad I didn't have a camera with me... should have taken a picture for you guys... anyone have any idea what type of pattern it was?