5. Google Insights for Search

With Google Insights for Search, you can compare search-volume patterns across specific regions, categories, and time frames. Here are a couple of my favorites:

• The Seasonality tool allows advertisers to anticipate demand for business at particular times of the year. It can show trends back to 2004 at the same time.
• Geographic Distribution allows advertisers to see search-volume distribution over cities and regions. With this tool, I learned that "football" was more popular in the UK, while "basketball" was more popular in the US. This could be important information if you were selling sports apparel or equipment in a number of international markets.