You have to hand it to Google. Their boffins continually come up with fascinating new ways to examine data. Although, with the amount of data that Google holds about the internet, and those of us who use it, it's hardly surprising that they're always looking for new ways to analyze it.
The latest idea is something called Correlate. You're probably accustomed to the idea of typing in a search term, and having a database system tell you how popular that term has been over the years across the web. Correlate works in reverse. Use your mouse to draw a graph, freehand, spanning the time period from 2003 to the present. Google then looks through its database of searches to find things whose popularity, over the years, most closely matches the curve that you drew.
In the example below, the shape I drew is shown in blue. Google's matches are then shown, and you can click on any of them to see more information. The closest match for the shape I drew was "css layout", the popularity data for which is then shown in red, superimposed on my drawing.
This innovative method of data analysis is fascinating. Look for things that have shot to prominence over the years, or for things where interest has waned. Or perhaps try drawing something a little more detailed, to find products and services which are popular only during certain seasons of the year.
You can try Google Correlate online at www.google.com/trends/correlate/draw. It's free, though you'll need a Google/Gmail account in order to sign in. You'll also need a suitable browser. Internet Explorer didn't work for me, but Chrome did. Now there's a surprise.