I read recently of someone whose notebook computer was stolen. The computer contained most of a book he was writing and he was beside himself with terror. No backup. No printed pages.
Nothing new, I suppose. I can imagine authors of old slaving away by candlelight, falling asleep at the quill and having the house burn down along with the manuscript.
Sometimes I imagine Blogger - if not the entire internet - disappearing into thin air because my book is a blog. There will be seven chapters and an introduction and half of each chapter is a blog post.
I printed out the first six posts - three chapters - delivered them to the commissioning publisher and breathed a little easier.