open source content management systems?

[r-militante at northwestern.edu]

hi all 
 
does anyone have any recommendations for good open source content
management systems for 
websites? 
 
i have about a 50000 page site running on a freebsd/apache server.  it
gets a fair number of hits a day.  
right now, the great majority of my pages are statically generated by my
30+ ftp users.  there is no 
consistency of layout between sections of the site.   
 
i wanted to investigate open source content management systems in order
to make our pages easier to 
create and update (preferably so i can do away with the majority of my
ftp accounts and have my users 
create and update pages from a webbrowser), and maintain a consistent
layout scheme across the site. 
 
i'd also be into investigating commercial cms's, although i'd like to
stick with open source if possible... 
 
thanks 
redmond