For development, you don't want any e-mail sent to the outside world, but you do want to be able to see all mail your sites or application try to send. Here is a configuration of Postfix to do that.
The trick is to BCC everything to a local user, and discard without error any other sending.
This is based on several guides and Q&As online but well, none of them worked for me, so here's exactly what i did (minus all the missteps).
Except where otherwise noted, content on this site is licensed under a Creative Commons Attribution 3.0 Unported License.