Once a company has a history of sales, it may need a database to track them. But as Jane Wesman discovered, a simple notebook may do the trick for tracking general trends. As head of Jane Wesman Public Relations, in New York City, Wesman keeps a business journal at home to record her personal reactions and never brings it with her to the office, where someone might be tempted to read it. The diary helps her run her business better because, by rereading it, she can detect trends that would otherwise be missed.

"For example," says Wesman, "my business journal helped me realize that it's almost impossible for me to close sales around Christmas. Until I recognized this pattern from several years' worth of journals, I grew anxious every year when business slowed near the holidays. Now I can stop worrying about that normal seasonal dip and prepare for it instead."