The recent rash of insider trading cases may be a shock to some on Wall Street, but not to one long-time market player: Bernie Madoff. In a Christmas Eve letter from the medium security federal prison in North Carolina where he is serving a 150-year sentence for running a massive Ponzi scheme, Madoff tells CNBC that insider trading has been around "forever." He also rails against what he calls a lack of transparency in the financial markets, and says the growth of hedge funds is forcing market players to take outsized risks in order to earn decent returns. Madoff has granted only a handful of interviews since he ... (full story)