It is good practice to use the special email address info@example.org as an auto-responder: people sending a message to info at your domain will receive a specially crafted automated reply to introduce them to your organization and give them pointers to frequently asked resources.
How to setup a Discourse topic to automatically reply with a pre-defined message?
(If this is possible already, make a step-by-step guide to set it up.)
What are the advantages of using Discourse for an info@ auto-responder?
From the top of my head, I can see one: Discourse can easily aggregate incoming emails and stage users, rewarding an “asked for info” badge so that you can easily target potential participants (and weed out failing addresses, or put them into a junk email filter.)