1. A vehicular rearview mirror-based navigation system, comprising: a rearview mirror system including an interior rearview mirror assembly, said interior rearview mirror assembly comprising an interior reflective element and an interior mirror housing for said interior reflective element; a global-positioning system comprising a receiving system; said interior rearview mirror assembly further comprising a global-positioning system display displaying information derived from an output of said global-positioning system receiving system, said global-positioning system display displaying scrolling information.