Hi All!
Strava (
http://www.strava.com/ ) is an online activity and performance tracker for those who cycle, run, or otherwise enjoy the outdoors and upload their Garmin, iPhone, or Android GPS tracks for comparison to others.
What caught my attention recently is Strava's "heat map" of cycling activity around the world one day, a nice little GIS exercise in graphically representing data.
The cycling "heat map" is here:
http://www.strava.com/saturday-heatmap#0|8|5|53.27455|11.97832
And a full explanation here:
http://engineering.strava.com/saturday-heatmap/Just click and drag the map to view other geographic areas.
Fun to see and lots of ways to look at the represented data. For example, in Oregon the bulk of activity appears to take place in the greater Portland metropolitan area (the state's population center) and in Bend, a known hotspot for outdoors activity in Central Oregon. In all locations, there is a time-dependency; not so many people ride at night as at Noon. Population dependances, too; not so many people are around to ride in remote areas, so the hot-spots are clustered around major population centers (cities).
Best,
Dan.