Nothing. You cease to exist. You will experience exactly the same condition as you did before you were born. As Mark Twain once said, "I had been dead for billions and billions of years before I was born, and had not suffered the slightest inconvenience from it."
What happens next once you die?
The Atheist Perspective
Do Muslims believe in reincarnation?
Answers: Muslim, Muslim
Why Pray? If it changes God's mind then he is not sovereign. If it does not change God's mind then it is pointless.
Do you hold to classical Darwinian evolution, or punctuated equilibrium, or something else and why?
Can justice be done using punishment of infinite nature for a transgression of finite nature?
Answers: Atheist, Christian
What is complexity science and how does it change metaphysical naturalism?
Atheist Hitler Homer Bible Christ: The Historical Papers of Richard Carrier 1995-2013 Richard Carrier Atheist Not the Impossible Faith Richard Carrier Atheist The End of Faith: Religion, Terror, and the Future of Reason Sam Harris Atheist God Is Not Great: How Religion Poisons Everything Christopher Hitchens Atheist Why I Am Not a Christian: Four Conclusive Reasons to Reject the Faith Richard Carrier Atheist Sense and Goodness Without God: A Defense of Metaphysical Naturalism Richard Carrier Atheist The God Delusion Richard Dawkins Atheist Humanism: A Very Short Introduction Stephen Law