Heat Maps

Steampowered.com shows some stats about the Half-Life 2 game. Most interesting are the Death Maps, showing where players died most often:

Looking at the data you can see where most people die. My guess is that this is good. These are places where some level of danger is introduced. And if the designers suddenly notice people dying in a place where they didn't introduce some dangerous thing, then you can know you have a game design problem.

I'd love to see this in a sandbox style game or a multiplayer first person shooter.