Since it's finally dry, I am now enthusiastically in love with my Dad's zeebee. I used exactly 1.5 balls of Nashua Wooly Stripes on size 9 needles. This made a soft, forgiving fabric with enough spring to make the hat comfortable. The color is called cognac, which is a blend of browns, silvery gray, and black. As the yarn name suggests, it is self-striping, but in a gentle way suitable for the rustic-looking single-ply yarn.
The zeebee is knit flat, sideways, with short rows shaping the crown. The two ends are grafted together to make it into a functional hat. The best part is that Schmeebot put together a pattern generator so that you can make them at any gauge and in any size you want. Brilliant! I will definitely make this hat again, it's so versatile and shows off the personality of yarn very well.