I love mustelid haberdashery, vinho verde wine, and wensleydale with fruit.
The third (and final, of course) installment in the Milkweed Trilogy by Tregellis.
In the previous book, our rather sad characters were stuck in their very depressing, very cold-war alternate-timeline future, and we discovered what the name the Eidolons gave Marsh meant, so he goes back in time to 1940 to work with his arch-nemesis Gretel to prevent the end of the world (as we know it, as it were).
I have to say, I'm rather surprised that this trilogy isn't more popular because the entire trilogy is very fast paced and tightly written. There are no points where we get bogged down in middle-book-itis or flounder around to create enough material for three books (since that's currently the "thing" for YA).
The characters are appropriately changed, the older Marsh is not the same as the younger (which he shouldn't be), the attempts to nudge things the "right" way without being entirely sure it would work are nice (even better when they don't turn out as planned). The emotional issues that would come from going back in time and seeing everything as it used to be, as you wish it still were.
It was good. Lots of awesome characterization, but still lots of actiony plot, and a nicely wrapped up ending that makes you feel pretty good about the whole thing, while not necessarily being a "happily ever after" for everyone.