My favorite shadow is just before sunset when I'm riding north or south. The shadow of the bottom of the tire and rim is about a foot long on the road and the rest of the wheel is a long oval going off the side of the road. Extra cool is when your shadow is long and thin until it hits some crops then it stands up straight and rides along with you.
Another cool one is when the shadow of the tip of your brake lever is right on the center of your front tire. Or when the sun is above and behind you and bits of your bike stick out from the shadow of your body.
I love my shadow. I ride the straight and lonely roads of Illinois.