a) wireshank - network protocol analyser (sniffer)
cain & abel - password recovery tool
jhon the ripper - fast password cracker
b) firewalls
anti virus
c) yes it is very good because users can acess this information and prevent any hacking, the only problem is by making this information public, is that hackers will start developing more programs to hack more computers.
d) definitely, prevention is better then cure, in other words administrators will be prepared for any attack on their computer, instead of being clueless and suffering the consequences.