The Appeal: You get to help people find the home of their dreams, and maybe earn big money. Plus, it's an easy field to enter. It takes just a few months of study to prepare for the exam, and voilà, you're licensed.
The Reality: Because it's an easy field to get into, there's a real estate agent on every corner. And most of your work is done at night and on weekends, when your friends are ready to play. Commission checks are shrinking because of discount brokerages and the softening housing market. And demand for agents is declining, since the Internet makes it possible to buy and sell property with little or no help from a professional.
Alternative: Sell higher-demand products that are less well known, like supplies to biotech companies or environmentally friendly goods such as fuel cells or pollution control devices.