For a while now, a few authors have been quipping at Zero Hedge that the best investment strategy is to do the opposite of what Goldman Sachs is telling is retail customers. The theory is that if Goldman tells the public to buy, it means that they are selling like crazy for their own account.
This seemed a bit cynical, but on Friday Zero Hedge observed that Goldman was telling its retail customers to buy European banks. This advice seemed so crazy -- the European agreement last weekly explicitly did not contain anything to help banks in the near term with over-leveraged bets on shaky sovereign debt -- that for the fun of it I played along. I shorted a couple hundred shares of EUFN, a US traded fund of European financial firms (took a bit of work to find the shares to borrow).
Made 6% in one day. Thanks Goldman.