Having just watched the London 2012 Olympics I used this wonderful resource extensively. To get backgorund information on all the countries in the world, and to lean of past successes and current prayer requests is very meaningful.
The opening maps and graphs also give one a world perspective.
Operation World is THE definitive prayer guide to the nations. I like the way information about the nations is presented and the prayer needs of every people group around the world. I use it regularly.