I also use a dokuwiki installation. It has lots of plugins like rendering to openoffice, pdf, presentation (s5 system). It has access control lists, code format

I also use a dokuwiki installation. It has lots of plugins like rendering to openoffice, pdf, presentation (s5 system). It has access control lists, code formatting, a hierarchical document system, it is very intuitive to use also. It needs php but no database.