I doodled my friends on my flights to and from LA (to see Depeche Mode). The likenesses aren't that great, but I did them pretty quickly, the first and third ones in about half an hour each. This is the first time I've ever tried drawing portraits from life!
The next one is a mini-doodle that I started in the hotel and finished up on the plane ride home (with no reference!):
I like drawing hair. Facial proportions are still hard, but that's why I need more practice.