Well 1st thing i want to tell you that this post is just for information purpose.
For any misuse the person doing it will be responsible. By this method you may send mail to anyone from any email address/name.

Like you may send mail to anyone from email addres jamesbond@us.gov

There are several fake mailers available on net.
You may even make youself. But here i would like to share a link

http://www.soom.cz/index.php?name=projects/mail/main

By this mailer u may send fake mails to anyone and you may even send with attatchments

So why waiting fo. Start pranking your friends