NYC Blog directs our attention to the map above, which depicts every street in the continental U.S. Map creator Ben Fry (no relation) posts a larger version on his site, and explains it like so:

All of the streets in the lower 48 United States: an image of 26 million individual road segments. No other features (such as outlines or geographic features) have been added to this image, however they emerge as roads avoid mountains, and sparse areas convey low population. The pace of progress is seen in the midwest where suburban areas are punctuated by square blocks of area that are still farm land.