Email notifications of replies to issues

I'm fairly confident that this will get marked as "won't fix", judging by attitudes that I have seen in forum posts regarding this topic and the fact that this feature doesn't exist yet, but I figured I should at least be able to say that I tried :)

I would love to be able to be notified by email when a reply is posted one of my subscribed issues on Drupal.org. I know there are scaling issues here, but in my opinion (uninformed though it may be), it's still a worthwhile feature, the lack of which sets Drupal.org apart from pretty much any other modern website that I can think of. The performance impact may be even less than you'd at first think, if this feature would prevent people (like me) from refreshing their issue queues tens of times per day (which involves serving lots of graphics and markup, compared to a brief text-only email).

Additionally, it looks like the pieces to do this already sort of exist individually - you can see when there are new replies to your issues in your own tracker page, and you can subscribe to email updates for entire projects, but not just your own issues across all projects. This leads me to believe that this wouldn't be terribly hard to implement, and again might not have any more of a performance impact than those features already do on their own.