I might as well add, Valerie got one that said it was GeekSquad notifying her that her computer was infected. (she bought the computer at Best Buy, so why not?) Same scam, big blue popup that doesn't go away. I get the Microsoft version now and then.

Pretty scary and they count on that.

Re-boot and it's gone. Some kind of website hijack that lets their scam invade and display the fake warning.