For the last four years, MotherReader has organized what she calls a 48 Hour Book Challenge: an unrestrained orgy of reading lasting 48 hours over the course of a weekend. It's that time again: that weekend when you can legitimately say, "Sorry, I can't. I have to read." The challenge this year takes place on the weekend of June 4-6, 2010. You can choose your 48 hours any time between 7:00am Friday and 7:00am Monday.