Magical Mathematics: The Mathematical Ideas That Animate Great Magic Tricks by Persi Diaconis and Ron Graham
A great read which takes some principles from combinatorics and shows how they can be used to produce some fantastic magic tricks. This includes the Gilbreath Principle which can be used to maintain some order in a deck when it is shuffled.
The book contains lots of interesting tricks, mathematical ideas, some juggling and lots of interesting stories behind some of the magicians of the day. I hadn’t realised before that there are people who can do a perfect shuffle on demand – take a pack of cards and spilt it in half, and then riffle shuffle the two parts back together so that the final order has alternate cards from the left and right hands.