Clark almost never puts a guest on the air, but a couple of times he's invited a personal finance columnist named Jonathan Clements on the show. Clements does a lot of great research into behavioral economics. One of his most recent articles addressed the age-old question: Are men or women better investors? It turns out women end up with less money over time because, as Clements argues, they're hard-wired to be conservative to a fault. They also live longer on average, so they have less money that has to stretch over a longer period of time.

Here's a disclaimer: This is a generalization, and there are differences from person to person. But generally, women tend to pick "safe" choices like CDs. Men, on the other hand, trade excessively and hurt themselves by buying and selling too much. Yet the average man ends up with a lot more money at the end of a working lifetime -- even accounting for income differences. If a woman puts money in CDs, she barely keeps up with inflation and loses in the long term. We are hardwired to fear loss more than appreciate gain. Clements suggests that we should each try to learn a bit of investing style from the opposite sex.