Forbes weighs in on the accumulator--or I-Kill-You-Later--scam in Asia. Wealthy investors are sold a derivative that calls for them to accumulate large blocks of shares of a Hong Kong-listed stock "every day for, say, 12 months at a discount to the share price. You could load up on lots of a $10 stock for just $8." Easy money.

The catch is that the accumulator contract terminates if the stock goes up only 5 percent or so, the terms get onerous fast if the stock tanks. You have to keep buying. If the stock drops below the discount price, "you have to double up how many shares you buy each day. If you don't have enough cash, the bank extends credit or demands that you pay up to cover the rest of your contract, often adding up to large multiples of your initial outlay." The likes of Goldman Sachs and Citigroup sold these products. Ouch! Like subprime mortgages, no one cared as long as the asset stocks were rising. 

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- here's the article