I'm having a hard time keeping up with these. I think I might be spending too much time on some of them. It has helped to develop some skills though, so I think I'd rather be behind than to hurry through them. This first one is a really bad caricature of Robin Williams, done with a skewer stick and drawing ink (fun technique).
This next one is Tommy Lee Jones done first with pencil and then with a Bic pen. I like going in with the pencil first. I have been trying to work on my exaggerations and that is hard to do straight with the pen. As you can see, I didn't finish the shading on this. It takes too much time.