How to Draw the Eyes

Stan Prokopenko just keeps impressing me!

Seriously, if you guys haven't watched these videos yet, you need to. I've seen a marked improvement in my own work since I started watching (and re-watching) these.

Previous videos in the series can be found here:
Head Part 1 (Any Angle):
Head Part 2 (Front View):
Head Part 3 (Side View):
Head Part 4 (Extreme Angle):