I'm part way through Sarah Moss's Cold Earth (published by Granta), a possibly post-apocalyptic tale about a bunch of grad students trapped on an archaeological dig in remote Greenland, while the rest of the world seems to be succumbing to a horrible super-virus. It's well done so far, but having the first 100 pages narrated by a convincingly drawn neurotic pain in the arse who it's difficult to want to spend time with may have been a bit of a tactical mistake on the author's part.
In any case, it's the cover I'm here to talk about.
Designed by Mark Swan, it has extra detail you can't see from this scan--spot-varnished root patterns growing out across the white from the central text block. Even better is the way that the edges of the pages are dyed a cyanotic blue.
This means that, as you read, each page has the visual effect of a slab of white ice rising up from an cold, clear blue sea.
I can't think of any other recently published book that has had page edges dyed in this way, but it's a surprisingly effective design element.
UPDATE: Alan Trotter informs me that "Scarlett Thomas' The End of Mr Y and PopCo have their pages dyed like this (black and blue, respectively)." (UPDATE 2: See his picture here.) And Thomas has a blurb on the front of this book. It's a dyed-page-edge conspiracy!
UPDATE 3: John Self brings back some causticity to this post in his comment, but also tells me that "Andrew thingy's [Davidson] The Gargoyle had black-edged pages hardback, and Tim Willocks' The Religion had red ones."
UPDATE 4: OK, obviously this is not as rare as I thought. Now Tom of book designers The Parish points out the design on Charlie Higson's Hurricane Gold: "The hardback ... also has gilded edges, and they are in gold. With nice embossing on gold foil on the cover, it's all gold!" And it is: