I'd like to have a very lightweight and easy mail transfer agent on my server. The only purpose of this MTA is to buffer outgoing email messages locally and forward them to ISP's mail servers.
What options Ubuntu offers?
Easy to configure for forwarding purposes
Simple - average user can understand how it works
Secure - outside traffic is disabled
No incoming email support needed
I have had various issues with sendmail and other complex solutions which are overkill for my modest needs.