What happened to Groupon?  This has been a terrible past week for deal of the day website.  The stock plunged 17% as the potential for an SEC probe rattled the share prices.  Groupon had the largest IPO since 2004, when our buddies at Google had a $1.7billion dollar initial public offering.  So what happened, well first let us hope that this is not another Enron or another episode of corporate malfeasance.  Initially the company came under scrutiny when before their IPO they revised their financials with the Securities and Exchange Commission.  The company came recently under scrutiny when an auditor...