The Hydrogen Sonata
by Iain M Banks
His final Culture Series novel before his death marks a very fitting end to the series. It covers the notion of Subliming, where by advanced galactic civilisations voluntarily dissapear into the "Ether" as they feel their time in the "Real" is finished. As such it has some qualities of death itself. I don't think Banks knew he had cancer when writing this book. Judging by the interview in the back of the book he was planning on writing more Culture novels. Sadly that will not happen.
One of the questions this book asks is do you tell your good friend and distant relative that the whole basis and meaning of their life was a lie just before they die. You know they have this suspicion, but still they believe they lie. Do you tell them or do you let them go to the other side believing a lie? Perhaps it doesn't matter even if you tell them. They like the lie too much.