The Wall Street Journal recently published a fascinating column on the best-performing stocks of the last 30 years. One intriguing feature of these enormous success stories is that so many of them are little-known companies in ordinary, sometimes downright boring industries: railroads, health insurance, back-office automation. The runaway winner, with a staggering stock price growth of 107,099% since 1985, was a truly obscure outfit called Balchem Corp., which makes flavorings and nutritional additives for animal feed — not exactly Google or Disney.