Want to do something with your cash but nervous about buying stocks in a choppy market? IBD’s Big Cap 20 list, which appears every Tuesday, contains stocks that have minimum market capitalizations of $15 billion. These stocks are less volatile than high-growth stocks like Taser (TASR), which can soar 10% one day and fall sharply the next. The behemoths in the Big Cap 20 are capable of producing steady — if not large — gains.