Every few years, someone reads, or remembers, or rediscovers something we often forget: computer memory isn't volatile, after all. Read More ..
RAM chips don't lose their contents immediately when you turn your computer off, and that can have interesting security ramifications.
Don't get too excited: RAM contents don't persist without power in a reliable and consistent way.
If you accidentally pull the plug out of the wall before you've saved that fantastic new presentation, don't expect to get it back.
But if you can cycle the power quickly enough, and reboot under your own control from some secondary device, such as a USB key, you might be able to see the ghostly remnants of what the previously-running operating system was up to.
You can guess where this is going.