I’ve just knit four trilobites into a hat.
It is Hannah Ingals’s clever pattern, available free in the Summer, 2009 issue of Knitty. Hannah was impressed with fossils studied by the paleontologist she lives with. So she reproduced them in stitches.
You can follow Hannah’s continued knitting adventures here. My recent version of her Trilobite hat is knit in Plymouth Yarn Encore Worsted.