Over the weekend I decided to configure my NetBSD system to stop sending emails to the local mbox (where I never read them) and start sending emails correctly to the internet. I also wanted to do so using my gmail account. Most of my info came from here but it's a little verbose for my tastes. Basically I had to do the following:

Now test with mailx someone@something.com and watch the maillog. I do get a warning about not liking the thawt cert, so I may figure out how to import it, but other tutorials all talked about needing your own CA and other insanity. I would hope the MUST in tls_policy insured that I was using SSL. I'll tcpdump and see sometime, but for now this seems to be all that's needed.

(Can we get SASL in base? I know LDAP, kerberos, and NFSv4 would appreciate it)

To fix the ssl cert warning, add the following package:
cd /etc/openssl/certs
mozilla-rootcerts extract
mozilla-rootcerts rehash

And add the following to your main.cf:
smtp_tls_CApath = /etc/openssl/certs

how to get individual gmail accounts/senders working is mentioned in this thread.