Number One on the list:
Metamorphosis by Franz KafkaRead the entire list.
An obvious place to start. A man wakes up one morning to find he's changed into a giant beetle. The transformation has already taken place when the story opens and Kafka offers no explanation as to why or how this has occurred. Instead he focuses on the trials of family life when you've become an enormous insect overnight. Needless to say, it ends in tragedy.