Another excellent book from Iain M Banks, who has an amazing imagination.
It is set partly in the real world, partly in a global virtual world that the inhabitants can switch between.
There is some good satire of hierarchical societies, in this case a kingdom, as the rulers react to global catastrophe by attempting to save themselves with no regard to the fate of the rest.
One of the characters can only spell fonetikli and tells his story in the first person but I found I adapted within a few sentences to reading many pages in his idiosyncratic style.