Eat My Sig
I'm quite tired of receiving email where the sender presumes they can force me to agree to some supposed license to their email by abusing copyright laws. I never signed their agreement, so unless you get me to sign an NDA in advance, I'll do what I please with the messages you send me. Tough beans. Let's use some common sense and common courtesy. If you're sending something confidential don't use email! If you have to use email, encrypt it! And check in advance that the recipient is, in fact, who you think it is instead of blindly sending messages and placing the burden of responsibility on the recipient.
As a response to these presumptuous signatures, I have written my own that simply states a few things that everyone should understand to be common sense for email communications.
-- As implied by email protocols, the information in this message is not confidential. Any middle-man or recipient may inspect, modify, copy, forward, reply to, delete, or filter email for any purpose. As the sender, I acknowledge that I have a lower expectation of the control and privacy of this message than I would a post-card. As a result, nothing in this message is legally binding without cryptographic evidence of its integrity. http://bilbo.hobbiton.org/wiki/Eat_My_Sig
As the signature itself implies, please feel free to use this signature on your own messages to express your own disapproval.