I’ve added a link to the another article to the support scam resources page: this one is by me for ESET, on the way support scams are gradually moving away from simple-minded cold-calling to fake-AV-like pop-ups, intended to trick victims into making the initial telephone contact. The scams are aimed not only at Windows users but at users of OS X and iOS, Android, and even (rather ineptly) Linux. How many Linux users believe their system uses an NT Kernel? (And no, Wine doesn’t either: it implements the App Binary Interface in userspace, not in a kernel module.)
Here’s the direct link to the ESET article: Tech Support Scams: Top of the Pop-Ups
And an article for Mac Virus expands on the cross-platform issues.