I was playing around with the Red Heart Super Saver Blacklight yarn the other day. Have you used it? It's black and neon and super bright. It also makes an awesome argyle!
The repeat of the variegated pattern is very long (it reminds me of the Super Saver Camo yarns) but I used a larger hook and it turned out to be a great scarf length.
So, for those of you that want to make a fun on-trend neon scarf with a little something extra (argyle!) I used a size I hook and my Argyle Crochet technique. Mine worked out to be 185 single crochet stitches long, and 17 rows. (You don't HAVE to use the argyle technique, it would still look cool as a variagated scarf). The finished scarf is approximately 63 inches long and 5 inches wide.