Do you write in the margins of your books?

Obviously, I have to ask this question after pointing everyone to the Times article on "marginalia", writing in the margins of books as you read them. (By the way, here's a link to another Times article on the topic, written in 2001. It's a different take on marginalia.)

I'm ashamed to say that I've never written in the margin of any book that I've owned -- not once. I can't imagine writing in a book. I mean, how dare I influence the next reader? I don't have that right. Sadly, I have been totally co-opted by the "misguided teachers and librarians" mentioned in today's article, the ones who said only barbarians would do such a thing.

I do confess, however, an almost irresistible urge to correct the typos in a book. I can hardly keep my hands off the pens when I see a typo. I am a Master Hunter and it is my Quarry! An urge to make the correction appears in my mind along with a fuzzy plan to send the finished book back to the publisher when I'm done with it. In other words, to be a real smarty pants. So far I've managed to resist this urge.

Do you write in the margins of your books? If so, I commend your aggressiveness (but I'm still not doing it).