Book Radio is up during the weekend, on Sirius.
I setup my SL2 to record all the weekend. They ran the first 5 episodes of Ender's Game during the wee hours. I've been unable to find any weekend schedule, though. The Sirius web site is useless...
www.sirius.com/siriusxmbookradio
Could somebody check if XM's 163 is actually up or not this weekend?