"How will you respond to the phone call?"
One day I got a call from an acquaintance.
He was utterly panicked because his Windows machine was showing him an FBI warning on boot-up.
I reminded him that the FBI has no jurisdiction in France, and told him to bring me the desktop.
I purged the unwanted malware with a Linux distro that boots on CD and told him not to go view pr0n on just any link.
Haven't heard from him since.