Submitting your vote...
- Asking "Are you here?" every minute or so when Skype status icon shows "Away" or "Not available". Isn't it clear that I am not here?
- Sending me "Undeliverable e-mail" reports. Spammers used my e-mail to send spam and I am getting tons of undeliverable reports. Some server administrators are incredibly... well, stupid... not to read this and still configure sending such notifications. I'll start to ban these mail servers on my server soon with corresponding error message.
Btw, it is a full moon today. Number of people, who behave strange, is incredibly high this time. Am I among them?
Basiclly it send incoming mail back to the sender with a "I am busy, resend this email in 5 minutes". If you are running your own servers I suggest giving it a try. If your interested here is a nice article on postgrey
http://www.howtoforge.com/greylisting_postfix_postgrey