Get rid of Spams
Spamcop.net is a very good site for fighting ever growing menace of Spams.
They have 4 services:
1. Reporting Spams - You can report spams sent to you and they contact server admins, ISPs where spams are originating and in somecases responsible ISPs block spams, so it helps blocking spams at source.
2. FREE BLOCKING LIST - They provide a DNS-based Blocking List which ISPs can use with their mailserver and get safe and effective spam filtering for free.
3. Spam-free email - Professional-grade SpamCop email accounts feature spam reporting, customizable spam and virus filtering and simultaneous Webmail, POP and IMAP access.
4. Ensuring your mail is not treated as spam - You can enter your IP and quickly check if your server has been reported for sending spam ever. You can find out if you are reported for spam and what you can do to ensure that your mails get through and not treated as spams.
I checked this service yesterday when our own emails were bounced by one of client's mail server. And they referred to this website as source; why they blocked our email.
But when I checked our SMTP server's IP was not blocked.
Further investigating this matter, I come to know that my email had traces of my PC's IP address which was dynamically assigned by my ISP. That DNS server (my ISP's server) was marked as "uncontactable". According to my knowledge ISP's dont allow their DNS to be contactable anyways.
Most important fact is that they should check SMTP server IP address compare to my PC's IP address to block spam.
Although these people are doing good job, other people bound to spoil the party by using it wrong way.