Are you interested knowing what people are searching using Google? Why not? If you are running a blog or a website this might be quite useful to identify strong keywords and weak keywords. Also that's one of the basic steps of Search Engine Optimisation.
I found Google Insights for search (Beta) as powerful tool when it comes to have an ideas what world is searching. You can compare by search term, location or the time period. You can do a simple query about "Entertainment Category in US for last 30 days and it will show you related search terms used in US related to Entertainment plus Rising Searches. Simply use a keyword like iPod or computer will give the Reagen in a map where that keyword is more popular. This is quite interesting tool if you are doing a blog or website for a targeted geographical locations.
Do you have any other Keyword search tools like this? What do you think about Google Insights for Search?