@derobert It was something along the lines of "Q: Can there be malicious commands in ~/.bashrc?" "A: sure, try adding rm -rf ~/*` to it, for example". Two minutes later: "Hey, I tried that command and now all my files are gone"
I don't think it's possible by kernel's default features. Kernel only supports hot-plug, but unplug. There could be a weirdo way to do this, but technically it sounds bad... there are few problems with this at least.