I've gotten counterfeit body wash (Shiseido Super Mild) and counterfeit microSD cards off Amazon, and, ironically, the only things I buy off amazon.com now are books.

Everything else I'd rather buy from the manufacturer (and pay the full shipping cost and not Amazon Prime) or a reputable distributor (digi-key/mouser for electronics, CS Hyde for films/tapes, etc).

Counterfeit items -- and the co-mingling of items "fulfilled by Amazon" -- ruined the whole experience for me.