Or to put it another way... we're a 2 person, self-funded, bootstrapped startup. Our most precious resource right now is the time of myself and my cofounder. Every minute we spend tweaking and tuning an email server, is a minute we're not talking to customers, doing market research, working on our product, developing strategy, doing competitive intelligence research, etc. For us, that's not a tradeoff that makes sense.
That and then there are periods throughout my day (especially at the $DAYJOB, like right now) when there isn't anything productive I can really do on the startup, and there aren't any pressing assignments, so reading HN is about as productive as anything else. :-)