Classical music is filled with child prodigies - heck, Mozart was writing symphonies by the time he was five. But the greatest names in classical music were almost all child prodigies: Camille Saint-Saëns, Claud Debussy, Gabriel Fauré, and many others (as a search of the archives here will show). A more recently prodigy was pianist Van Cliburn who won the very first Tchaikovsky Competition in Moscow back in 1958 - the judges had to ask Khrushchev himself for approval. The response: "Is he the best? Then give him the prize". Cliburn started playing piano at age 3.
We may need to add to this list. Elisha Mysin is a Russian prodigy. Now six (there is some question about this), this performance of his was recorded when he was five. It is, as you'd imagine, quite impressive.
The Queen Of The World spotted this on the Book of Faces and brought it up, along with the idea of talking about child prodigies. She's pretty dang sharp (not to mention pretty as a picture).