People are recieving a bounceback from 'spamrats' when they attempt to email me. Help! 

Spamrats is what is known as a 'Global Blacklist'. If someone is recieveing a bounceback from QWK.net mentioning spamrats it means that an IP Address between you and them has been blacklisted recently for sending spam, or the people sending to you are not conforming to best practices for sending email.

Feel free to refer them to http://www.spamrats.com/removal.php where they can work on getting themselves removed from spamrats. QWK.net chooses to use spamrats to limit the amount of spam that gets through to our customers, but obviously every anti-spam measure is going to block a good message at some point. QWK.net cannot remove this block without affecting all its customers.