What's the Secret of Smart Budgeting?

You've probably heard the saying "the devil is in the details," but when it comes to managing your money, just the opposite is true – the more details, the better your chances for success.

I recently interviewed Stephen Spiller, a PhD candidate at Duke, who has a forthcoming doctoral thesis on opportunity cost, and how it relates to the way we spend money. In layman's terms, opportunity cost is the benefits you miss out on by making a particular choice. Let's say you get a $1,500 tax refund...