TripTrop NYC:

Enter any NYC address into TripTrop NYC and you get a heat map showing public transit travel times to other parts of the city.  For example, the map above shows average commute times for various neighborhoods if you worked at Rockefeller Center.

The only thing I don’t get is the rationale behind the rectangular shapes - wouldn’t it be more rounded, or aligned more to the road grids, like water dripping through concrete?

(via joelaz, Cal)