Studying brain plasticity for a psychology course has reintroduced me to my fascination with autistic savants.
My favorite story about such a case is the story of Leslie Lemke. I do not think that I can do this true story justice with any sort of synopsis, so I will leave it in the capable hands of Cloris Leachman, and an ABC Afterschool Special: The Woman Who Willed a Miracle--which I was delighted to discover is freely available on Youtube in 5 parts.
If that peaks your interest, I highly recommend watching the original Canadian interview that inspired it: May's Miracle.