sorry to necro a thread!
I'd just come across an interesting, albeit new-agey at times article on the therapeutic benefits of knitting.
knitonthenet :: Therapeutic Knitting
I'd like to come out and say I started knitting therapeutically to distract myself from my headaches. I've been getting bad headaches for years and so far knitting has been prettey effective. I'm all just like "I can't think about pain right now! I have yarn overs to do!"