What a shame, the Book Pillow is no more – they have discontinued production. There’s nothing else quite like it on the market as far as I can see, although there are similar things for i-pads and e-readers, but they don’t look as good.
This isn’t exactly an accessibility thing but I think lots of people would find a book pillow useful! They are really light and both prop your book and help keep it open. Highly recommended!