if I have time I read ai related articles, and found somewhere car + pedestrian traffic simulation softwares, simulation of crowd on street and flowing out of buildings...

one of them is called as continuum crowds... as I know these systems usually work with potential fields.

and there are open source projects too at some universities... but this is much more than simple game ai...

maybe I have some links bookmarked, if you need just send me a message and I'll try to find it.