I'm quite surprised not to find any other thread on this. If a thread already exists, please let me know.

This is very impressive: http://ubuntustats.com/.

You can follow in real time a representative chunk of the Ubuntu community activity, all in one web page. You can personalize the way data is shown.
Congratulations to Martin Albisetti and Felipe Lerena

Linky:
http://beuno.com.ar/archives/28