A better TriMet city center map V1.2
Unlike the official map, bus lines are colored in more than just gray. In this map, all lines that share a set of stops on 3rd (A, B or C) or 4th (X, Y, or Z) have a specific, individual color. In addition, some (other) lines use Jefferson/Columbia and are divided between two stops near 5th and I tried to give lines serving each of those stops their own colors, too.
This map is also available in SVG format at Wikipedia
Updated to reflect August 31 changes as well as fixing various stops