Today one of my children learned the first rule of computing: always save your work.
The aforementioned child was working on an essay, got bored and wandered off. An hour+ later a sibling started to use the computer and the dang thing got hung up. I tried saving the essay, but it was well and truly locked up. All I could do was restart the computer.
There was much sadness on the part of the essayist and a lecture from me to the effect that you should regularly save your work and don't wander off. Luckily I was able to recover the essay and got the title of "Best Mom in the World." I just hope that the lesson was learned and we won't get a repeat.