Yarn: Caron Simply Soft.  Main color: 3 skeins (6 ounces each) dark blue.  Contrasting color: 1 skein (6 ounces) gray.

Needles: Machine knit on bulky gauge machine

Other tools: ball winder

Gauge: Tension #3.  32 st x 20 rows for a 4" swatch (or 4 st per inch)

Finished object: measures 94" x 7.5" not including fringe!  wow, that's a huge scarf!

 [click pic for enlarged view]

Pattern Notes:
This was done using a ribber attachment (1 x 1 rib).  CO 29 st on main bed and 30 st on ribber.  
Tension #3.
Trapped bar pattern:
Knit 24 rows in MC (main color)
Knit 2 rows in CC (contrasting color)
Knit 3 rows in MC
Repeat x 14 times (or as long as you want the scarf).
Knit 24 rows MC.
BO all stitches.
Add short fringe in MC.

Comments:
I'm trying to write this description long after I finished the scarf, so I don't really remember much.  My notes say this is the one from the Harry Potter Movie Prisoner of Azkaban.  The Caron Simply Soft IS very, very soft and also cheap and easily available.  You can find it at Wal*Mart and Michaels.  The scarf itself is gigantic and weighs quite a bit.  I could have done a better job with weaving in the ends.
Machine knitting is super quick.  This scarf took about 2 hours to knit.  It would have been faster if I already had the pattern, though!  As the material is a 1 x 1 rib, it lays flat and doesn't curl under.