It also depends on your shoe size. I have really big feet, so even ankle socks would be a no...
I'm using it now to make a sock. It makes a good, stretchy fabric. =)
If you're worried about yardage, what I've tried doing is measuring a yard at the beginning of a row, tying a LOOSE knot there, then when I reach it I know approximately how many rows and stitches one yard can get. That can give you some idea of how much you'll need. Be sure it's a really loose knot so you can undo it, of course
