The World War II Museum, Knitting for Veterans Campaign is a hugh success and still going strongly!  They have new 2009 - 2010 Scarf Patterns for both knitting and crochet.  Both are in pdf format:

September 8, 2009 - Update - 2009 - 2010 Scarf Patterns:

2009 - Chevron Scarf Knitting Pattern:

http://www.nationalww2museum.org/calendar/2009-scarf-pattern-knit.pdf

2009 - Chevron Scarf Crochet Pattern:

http://www.nationalww2museum.org/calendar/2009-pattern-crochet.pdf

September 2, 2008 - Update - 2008 Scarf patterns 

2008 Lengthwise Striped Scarf Knitting Pattern:

http://www.nationalww2museum.org/assets/pdfs/2008-scarf-pattern-knit.pdf

2008 Lengthwise Striped Scarf Crochet Pattern:

http://www.nationalww2museum.org/assets/pdfs/2008-scarf-pattern-crochet.pdf

They have 2007 Scarf Patterns for both knitting and crochet, featuring a ”V” for victory on them.  Both are in pdf format: 

2007 Patterns:

2007 V Scarf Knitting Pattern (designed by Lauren Handley)

2007 V Scarf Crochet Pattern (designed by Rachel Vives)

(Original post about WWII Museum Knit Your Bit Campaign is here.)

Lion Brand Yarn also has a touching story by a woman who knitted a scarf for this cause.  Her story is here.