It matches my dog! It's Urchin, by Ysolda, and it's quick and easy and interesting to knit and holds its shape beautifully. Some more pics, to show the shaping:
It's also a great example of why Ravelry's the best invention since circular needles. The wool was a present, but I only had one skein; I searched high and low for another in the same dyelot, because all the slouchy beret patterns I had used more than one, but no luck. Then I searched on Ravelry for a one-skein beret pattern, and this popped up. I made it with 10cm to spare, leaving out the last wedge in the pattern.