Man I would freak OUT if I came across a random, spontaneous 'Zombie Walk.' The area in which I reside has a conservative streak a mile wide, so I doubt it would ever happen. But how cool would it be to see apparently random 'strangers' eaten by zombies and turned into the living dead themselves? From wiki:
A zombie walk (also known as a zombie mob, zombie march, zombie horde, zombie lurch, zombie shamble, zombie shuffle or zombie crawl) is an organized public gathering of people who dress up in zombie costumes. Usually taking place in an urban centre, the participants make their way around the city streets and through shopping malls to a public space (or a series of taverns in the case of a zombie pub crawl) in a somewhat orderly fashion.