For anyone who has ever received an email that has either been sent to multiples of people or forwarded from many before getting to you, you’ll understand what I mean.
Hide the email addresses of your recipients!
This is how alot of email addresses end up on SPAMMERS (senders of unsolicited emails, like the Viagra ones) hit-lists. There’s also the possibility that if even just one person of those you e-mailed gets an e-mail virus, every person on that list is at risk of getting it. E-mail viruses check for ALL addresses that person has in his/her e-mail.
So the best way to send an email to many recipients is to send it using the BCC (Blind Carbon Copy) option. It is available in 99.9% of email programs/clients and website-based email.