Investment Ran Out of Energy

My dumbest investment was buying into a fuel cell maker at $32 per share after it fell from above $100. I didn't pay attention, and it collapsed again, to single digits. I did no research. It just seemed like a cool local company with a good product. Its management seems to have changed their strategy for the better, so if they survive, I might get my money back in… who knows how long. Do your research!

— B.G., online

The Fool Responds: You were right to consider a local company, because those are often the ones we know best. You might, for example, have friends who work there and who have a sense of how the firm is doing within its industry. You were wrong, though, not to do any research into it. Alternative energy is an important and growing field, but not every company in it will prosper. Look to see which firms are growing their sales and earnings, have little or falling debt, have a strong competitive position, and are not depending on a single product for revenue.

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