I have a residential ISP (the cable company) and fetch my mail via POP3. I can check my email anywhere, but I can only send email from within their network, in the same city. If I take my laptop out of town or to a hotspot that uses the other major ISP in town (the phone company), I cannot send email.
I am currently in the process of frankensteining an ancient laptop to act as a personal webserver. Does anyone know of a very small linux application that can accept SSL'd and Authenticated ESMTP connections and forward mail on to the ISP's outgoing mailhost? I'm looking for something similar to ssmtp, but able to accept SSL ESMTP AUTH connections. There will be no scripting interpreters on the laptop, so PERL, Python, Ruby, etc are out.