It is such a pleasure to leaf through a book - the one I am currently dipping in to is David McCandless' "Information is Beautiful". Data is taken and displayed delightfully, beautifully even.
Having data available makes such books possible and the skill (art?) of reproducing the data visually makes the point easily, much more easily than the raw numbers would have it.
I notice data being put to good use in London. Boris Johnson (Mayor of London) had London data put on a website - London Data Store - for free. And the result?
Smartphone apps which tell you where the nearest toilet is or where you can find the nearest docking station for your hired bicycle.
Entrepreneurs have produced the apps using the raw data now available.
What else can you do? See traffic cameras, rate hospitals by their bacterium infection rate, determine air quality, and even have an app which wakes you up early if there are delays on the underground tube system.
And the possibilities are very many - crime is easy to trace via pages of data regarding stone throwing by London borough, robberies, knifings on trains, etc.
Apps are everywhere in London - I even saw a policeman whip his i-Phone out to show an enquiring lady which way to go.