Wow. I never thought Enron would be matched or surpassed in terms of balance sheet gimmickry, but it seems that Lehman accomplished just that according to the court-ordered report on Lehman's demise. Dylan Ratigan does a great job explaining how Lehman accomplished this feat:
Along these lines, Frank Partnoy makes the case that financial firms still doctor up their balance sheets--though not as deceptively as Lehman or Enron--primarily by use of off-balance sheet accounting tricks. These "balance sheet fictions" as he calls them were an important part of the financial crisis (e.g. SIVs) and he wants them to be addressed by financial reform legislation too. Partnoy argues that unless the abuse of off-balance sheet accounting gets included, financial reform will not work. Here is a short video clip where he explains his concerns.