Just a quick post about this really, Kayleigh from Couture Girl wrote about her friend being conned into buying some fake MAC make-up. I also did the same thing a few years ago when I bought 4 pigments off of ebay, I only knew something was wrong with the products when I tested the colour on my hand and you could barely see it, the pots of pigments sell for quite a lot of money and are raved about by lots of make-up artists so I looked into it online and finally realised they were fake. Until that moment I had no clue there was even such a thing as fake branded make-up! It is terrible that this happens and so many people get sucked into buying these products, because like me I imagine they have no idea that fake make-up exists!
If you would like more info on how to tell a fake then pop over and read Kayleigh's post here.