((originally adapted from this pattern))
Oh My Yes! Found this over at One Sheepish Girl and, I have to say, I am smitten; both with her blog and with her choice in granny style collar.
Sporting a Peter Pan Collar
Here are a few more collar patterns:
Mel P Designs Crochet Pan Collar
Knit Pan Collar via Reckless Glue
and, if you're not knit or crochet inclined
DIY Felt Peter Pan Collar via Honestly WTF