Haven't been by here in a while- see you've kept busy! the zebra in 310 made my day- I have an affinity for zebras ^_^.
The caricatures are fun- I found they really helped me understand the structure of the face as I played around with them. I agree with the above where you say women are a pain to do. I find young, attractive women to be my least favorite thing to draw. Their face is too boring. weird looking people and old people are the most fun to draw. Their face just has so much more to play with.