Maybe Goldman Sachs. Manipulation of many markets, both contributed to and profited from the 2008 crash. Which they paid a $550mil settlement for when they're like a $100bil company. Imagine making $50k a year, committing fraud ("misleading its investors") at a national scale affecting millions, and getting fined $250.
Also manipulation of gas prices, food supply/prices, insider trading, they're just the freaking worst.