# Allow everyone and everything
ALL: ALL 

# Anyone in same domain or in moo-u.edu domain
nfs : LOCAL @moo-u.edu  

A specific user and any host in cows.moo-u.edu 
telnetd : barney@moo-u.edu .cows.moo-u.edu   

Most everyone for ftp.
ftpd : ALL EXCEPT hacker@moron.org