I often use existing patterns and modify them for the yarns and needles I am in the mood to use at this point in my life. Sometimes I am in a chunky mood (please, I am talking about yarn!) and sometimes, like now, I want to knit with a thinner yarn. However, I always give full credit for the idea to the original pattern designer and only if the pattern is free. Plus I got permission from the designer to post the link. Thank you Jen!
So the link to the original pattern is http://www.ravelry.com/patterns/library/brainwave. Copy this into your address bar and it should take you right there.
For this pattern I used Woolike from Loop and Needles. It is 100% acrylic so if you are allergic to wool or other natural fibers, this is the yarn for you. It has the feel of an alpaca lace yarn so it is extremely soft.
I used size 2 circular needs for the brim and Size 4 for the body of the hat. I cast on 128 stitches. You can use any number of stitches as long as they are divisible by 8. I just love the cable ribbing and it is stretchy enough for any sized-head. I also did not do the return wave but I think I will on the next hat. The cable rib on the brim is so much fun too. I might do an entire hat in that pattern in a future hat.