"I want a Star Wars hat!" he declared a month or so ago. Confident that Ravelry would provide in abundance, I promised with wild abandon, "Sure, bub, I can totally do that."
I had to Frankenstein two patterns together to ultimately get what I wanted, but in the end I was not wrong.
The base hat is the classic Clayoquot Toque from Tin Can Knits. It's the same hat I made for the Kid last year, so I was confident with gauge and sizing. The R2D2 chart is here. If you do the "adult" size of the hat (but make it just a little shorter) the chart divides perfectly into the number of stitches and you don't have to do any fiddly math.
(A joke about Han Solo making the calculations to jump to lightspeed seems appropriate, but I'm sleepy.)
May the force be with you.