So if you're a hotmail user, consider enabling that option and giving some money to charity just by sending e-mails.
I'M is a new initiative from Windows Live Hotmail that shares a portion of our advertising revenue with some of the world's most effective social cause organizations. For every mail you send from Windows Live Hotmail, you help address the issues you feel most passionate about, including poverty, child protection, disease, environmental degradation and animal protection....You'll be making a difference and there's no charge to you.
The program is called I'm making a difference. As of May 14, 2008, the site claims $1,494,480 has been raised so far.