This is the famous Foliage hat. It's such a simple pattern, but the effect is great. I chose Lang Merino 70 Superwash yarn for this, which is a merino extrafine with a tiny bit (2%) strechy polyester mixed in. It's soft and is definitely a great choice for a hat.
With the left skein of yarn I decided to make a scarf/neckwarmer that would go with the hat. Initially I wanted to improvise and just use the foliage pattern for a scarf as well. But then I did not feel like thinking too much ;-), so I chose Branching Out. The sentence that convinced me to go with this pattern was this: "Gauge is not crucial." This meant that I could stick with the same yarn I used for Foliage and have a matching scarf.
I knit both on 3.5mm/US 4 circulars (really, I use circulars for everything). I'm sure I'll use Foliage pattern again. After all, my sister also wanted a hat. ;-) I'm into accessories and want to knit loads of hats, mittens, wrist warmers, scarfs, etc. and totally dream of this. Oh yeah, I still have a free wish for my birthday!