Riddley Walker is a good contender for my all-time favourite novel. It’s a post-apocalyptic story told in the first person, with altered spelling and reinterpreted expressions and the rhythms of oral history to match. The language is at first intimidating, and it’s a testament to Russell Hoban’s writing that you get caught up in the flow so quickly, so that by the second chapter you’ll only notice it’s unconventional when you get the thrill of deciphering something new. (I can imagine it could be substantially trickier for second-language English speakers. Anyone who is having difficulties, though, should try reading a line or two aloud — I’m sure this is deliberate, since doing so will also make you appreciate the storytelling rhythm and flow much more clearly.)

Thanks to a LibraryThing review by princemuchao I can point you to the Riddley Walker Annotations project, which is marvellous. Only don’t visit it if you haven’t read the book already, you’ll spoil all that lovely discovery!

It turns out that Russell Hoban also wrote a book that I loved as a child: How Tom Beat Captain Najork and His Hired Sportsmen, illustrated by Quentin Blake, which I also recommend most highly.