Facebook. I googled and found that there is a scam trying to get you to an outside website in order to get some malware on your PC. There have been several such scams and currently they ask for £3.99, funny as the pound is a British currency and Facebook is American.. $3.99 is what I would have expected.
So why are people afraid of Facebook asking for a monthly fee? Maybe this is because its "value" of multiple billions of dollars cannot be explained. Much of it is in its ability to sell adverts, to sell information about people and because it takes your data prisoner.
The high valuation of Facebook is tolerated because of its growing audience and its growing traffic. It is about to subsume the Wikipedia content and what is of no monetary value to the Wikimedia Foundation will become valued and monetised traffic sustaining Facebook. There are similarities with a pyramid scheme and when this proves to be the case, the high hat will not have money popping out but a customary bunny.