I have a MacBook pro running Lion. Usually, I need to run tasks that takes hours... so I just leave the laptop working before going to bed.
When I wake up, I notice that it tried to shutdown the system. How do I notice this? Well... all apps are closed except for iTerm (which always stops shutdown process when there is more than one tab open).
I tried to search the energy saving settings but there is nothing related to this... I would like to see how to prevent this behavior.