Recently, JP Morgan reported rather biggish losses due to only a few trades/positions. According to rumors, hedgefunds and speculators already took a piece of the cake, since positions are not closed yet. It's not completely known which these are, but apparently they involve the the IG9, a credit default swap index including 125 american companies. You can find more information on it at markit CDX and their product description page. Basically, it's one of the largest and most liquid CDS products. You would want to buy these products to hedge risk on bonds issued by the companies included in the index. Conversely you sell it, if you want to bet on the solvency of the companies. In this case, you get some money up front for selling it and a continuous payments during the contract period (10 years). As soon as a company fails to meet its liabilities, the total loss on the company is calculated, e.g. if the company recovers at 30% after filing for bancrupcy, the 70% loss is mutliplied by the weight of the company in the index (all have 0.8%) gives the amount of money you need to pay to cover for the losses.
Moreover, these products create a leverage and thus opens the possiblity to hedge delta trades by buying on the index. Apparently, this kind of trade caused the problems at JP Morgan. As far as I know, there is no easy access to these products using your everyday discount broker.
List of links to news regarding JP Morgans trade: