A wonderful system I have seen used in diverse places is a carousel projector, providing ever-changing names/logos/etc. Easy to change out or add names.
Challenges include mounting so as to be out of reach, and the need to project into a darkened corner or floor location. Advantage (in addition to ease of update) is the fact that people will stand and watch the display for several minutes, as opposed to walking by a wall display with a cursory glance.
Liz Bleiberg