For a while I was trying to read my apache.org mail through gmail, but using a web interface to read mail just didn't agree with me.
However, their service is useful after all! The new POP service comes with authenticated SMTP as well, so without having to enable POP you can use smtp.gmail.com (enable SSL and use your regular gmail username and password) to send mail. I've been using it for a few days for some of my mail and it seems to work alright. (I had one mail that either disappeared or got delayed, but everything else has been passing through their system in a few seconds).
update: eh, Evan pointed out to me that it's not that cool at all. Either I didn't pay attention when I tested it first, or they changed it in the last few days. See the comments.