ANOTHER BIG NO-NO
I just remembered this very important thing also....
If you ever receive any of those emails that promise you free this and free that if you forward the email to your friends, they are just scams. Microsoft, Coke or whoever do not have a way of tracking how many people you forwarded the email too, it's just a way for the scammers to clog up the internet with junk mail, and also most importantly a way to harvest email addresses.
For example, if someone sends you one of these emails, they probably sent it to 50 people with all 50 addresses in the To list. That means you now have access to the email addresses for all 50 of those people - if you are a scammer that will make you happy.
However - if you forward that email intact to 50 of your friends and use the same technique (use the To address for all 50 names), then each of your friends will know not only about the other 50, but they will also have the 50 names that were sent to you.
I have seen emails forwarded ad infinitum and containing as many as 1,000 addresses. It only takes 1 scammer to guarantee your email address is added to a junk mailing list somewhere.
Also, it only takes 1 of the computers that has received a copy of that email to get infected by a virus, and it could be even worse.
I have 2 pieces of advice....
1. Unless you absolutely feel you have to pass it on, chop out the bits with other people's email addresses first.
2. Send to your friends using the BCC (Blind Copy) addressing option. Blind Copy sends the message so that each recipient only sees their own address and yours.