Google.org is now offering a data mining service called Correlate, which enables users to find matching search trends. For example, you could use your own name and find search trends that show similar increases and decreases in search volume (well, you would only do this, if you are really popular.) Alternatively, you can upload your own data series and match your data against correlating search trends on Google.
Of course, there are few limits to this technique and you may find surprising search trends on particular days as the data is presented in real time. You can either choose to show the data on a time line or visualize it depending on search distribution in the U.S.
So it is not just a feature that you can use for presentations and surprise your listeners with the fact that, for example, spaghetti are closely related to brown pants. There is an interesting social behavior implication and I am sure than marketing will find this tool very useful.