Downtown Chicago
courtesy of Chicago CartoGraphics

Downtown Chicago pedway and cut-throughs

courtesy of Chicago CartoGraphics

Chicago area expressways and traffic report names

courtesy of Chicago CartoGraphics

multilevel streets of downtown Chicago
the complex levels and ramps of Illinois Center and Lake Shore East

2018 aerial photos for Cook County
late spring (leaf-off) aerials better allow roads and structures to be seen

“paper” USGS topographic maps online
choose Scanned Topos in upper right corner

Chicago bike map online
bicycling facilities and routes shown on Chicago CartoGraphics base map

Chicago rapid transit map
all routes, even the crowded Loop, integrated into a simplified map

Transit isochrones
how far you can get by transit in a set amount of time

Home prices
data from Trulia

Public art
outdoor installations in the City of Chicago

Employment
nationwide map of where jobs are located

City of Chicago 80-acre cadastral map viewer
alternate search by PLSS section

Chicago neighborhood map
A map of neighborhood boundaries is inherently problematic, for reasons described here. But if you're determined to have one, this 2008 PDF from the city seems as good as any.

“Populated Places” of Cook County
The national database of map locations includes some parts of Chicago whose names are unfamiliar, even to natives.

Chicago street guide
PDF showing all Chicago streets with house numbers (2600 N, etc.)