Recently, I was assisting a student who was looking for data on cell phone use. I was reminded of this site, GapMinder. They have interactive data on hundreds of topics and sure enough, they had cell phone data from the UN. The data could be downloaded as an Excel document, viewed on the web or in a visual interactive display. This was just what the student needed.
Check out the visualization of cell phone data here.
What are some other resources online for finding and analyzing real-world data?