2. Main Street Capital ( MAIN) is a business-development company, investing in small and middle-market companies. Its second-quarter distributable net investment income surged 131% to $5 million, or 33 cents a share. Revenue more than doubled to $8.7 million. The operating margin contracted from 81% to 78%. Main Street pays a quarterly dividend of 38 cents, translating to an annual yield of 9.1%. It carries $4.7 million of cash and $139 million of debt on its balance sheet. The stock has delivered three-year annualized gains of 3.8%. It is flat in 2010.