Iconic coffee chain Starbucks (SBUX -0.41%) has been a life-changing investment for many. The Motley Fool's co-founders, David and Tom Gardner, famously picked the stock on daytime television back in July of 1998. Had you invested $30,000 back then, it would be worth over a million dollars today.The shares aren't so hot right now, trading near their 52-week low. But the market can be irrational from time to time. Buying good companies when they're unfairly out of favor with Wall Street is a great way to mak ...