How engrossed do you get in a book?

One day, when I was maybe 20 years old, I took my mother downtown. While she went shopping, I sat in the car, which was parked along a busy street in Jacksonville, Florida. While waiting for my mother to return, I read a novel. I guess I was pretty engrossed in it, because all of a sudden I heard sirens. I looked up and there were fire trucks parked between me and a house that was on fire. I couldn't believe my eyes. Had I woken up from a dream. Nope. It was real.

How about you? How engrossed have you gotten into a book?