Whitelists to block spam

So far I have been really happy with Spamnet as my solution for blocking spam. But in chatting with my friend Elya, he has also been employing some other solutions to address the situation.

His comments:

i use frontbridge,
there is also clearmx.com,
bright mail

> set querytype=mx

> fddi.com

    Server:         127.0.0.1

    Address:        127.0.0.1#53 

 Non-authoritative answer:

fddi.com mail exchanger = 10 mail.global.frontbridge.com.

so all of my email gets cleansed before it hits me
and then i just use postfix header checks to get rid of the blank spaces in subject lines, email from .jp and other domains
and anything else that the spam organization doesnt clear up

yeah. thats the next big thing for the internet
spam and fortigate boxes
i'm playing around with http://www.tmda.net

Q: tmda is what you are using for the message I just got?
can you use it on just a single mailbox?


A: yeah thast what im playing with
tmda is on the server
what prevents someone from spoofing my email address
and you can enable it for anymailbox
by modifying your .forward.

postfix...
nobody can spoof bc i use postfix sender checks
and smtpd_recipient_restrictions

http://tmda.net/faq.cgi?req=all has a lot of info

Q: cool, but u need a linux box... can't do it with exchange

A: yeah. nobody has ported it yet
im actually trying to get it to work on exchange
it uses python.
There are ones that you have to pay for though
http://tmda.net/faq.cgi?req=all#1.9