This is by far my most favorite hat pattern.
It's the Dean Street Hat and it's a free pattern on Ravelry (free is always good, isn't it?)
I used Lion Brand Wool Ease worsted weight washable wool. The yarn doesn't show the cable pattern as well as I would like, but this hat is a gift and I wanted it to be an easy wash item. I think the cables show up well enough for me to recommend the yarn and it's very easy to knit with. It's one of my faves.
One thing I love about the pattern is that the author/designer, Nina, instructs you in cabling without a needle. It made the hat knit up very quickly! I'll probably knit many of these hats. The designer has other wonderful patterns available, too. The Vita Cloche and the Faberge Cowl are on my queue!