Jack Maggs question

As someone who has recently written a short story very much inspired by 'The Raven' by Edgar Allen Poe, I've always been interested in texts that riff of a famous work and make it into something very new and different. Jack Maggs was a great example for me of how a really good new story can be found by following the life of a character in another novel.

Another one that really stuck with me was the play 'Rosencrantz and Guildenstern are Dead' by Tom Stoppard. Part Shakespeare, part Beckett, and fantastic as a result.

Just wondering if anyone has any other recommendations/thoughts on great works that incorporate characters from classic texts?