Without Login To Your That Accounts?
Here is The Way:-
Open The below link
https://mail.google.com/mail/h/0/h/
Select Settings.
1. Click the Accounts and Import tab.
2. Under Send mail as, click Add
another email address.
3. In the 'Email address' field, enter your
name and alternate email address you
own.
4. Enter the SMTP server (e.g.
smtp.domain.com), your username on
that domain, and your password for
that account. You may also need to
adjust your port setting or SSL setting
(talk to your other ISP if you need this
information).
5. Click Add account >>
6. Open your other account and either
click the link in the message Gmail
sent or enter the confirmation code in
the Accounts and Import section of
your Gmail settings.
Now you can send email's to your all friends
with your own desired email address
without signin to that accounts