The Crain Communications Building is the slanted-roof tower facing Millennium Park, easy to pick out from Michigan Avenue and the riverfront. Its angled top is lit at night, which makes it more memorable than many taller Loop office blocks.
Architecture fans may also know it from film appearances, but the main pleasure is simpler: it is one of those Chicago buildings that gives the skyline a bit of wit. Look for it while walking between the Chicago Cultural Center and Millennium Park.