There is nothing more irritating for people who get a lot of email every day, than to get these "Look at this cat on piano video" emails from n00bs and well-meaning grannies, but enough is enough.

We all need to educate all users of email, especially those who have our addresses in the use of BCC. Not only do I not necessarily want everyone you know to know I know you, but the practice of CC in the clear opens all of us on the list to several kinds of abuse.

Ironically, there are commercially-driven people who refuse to stop the practice even when you ask them to do so. 

First and foremost, you need to explain that when an email is sent out to 50 people on a CC list, if one of those people gets a virus, it often will grab all the addresses, mail copies of itself out to them AND call home adding you to the huge spammer database list.

There are many reasons not to use CC with long lists or to a group of people who do not know each other. It's a faux pas, please don't do it.

Use Spamcop.net, procmail, spamassassin and sendmail basic tools like the access file to block and report spam. Unfortunately, it's the CC that put you on the list in the first plave.