In addition to our previous email support, we now offer question owners the ability to receive email notifications of new answers to individual questions.
It's a new option at the bottom of any question you've asked:
Ticking this box will enable global email notifications in your account preferences, and entering an email address here is exactly the same as updating it in your profile. (This will soon be extended to the /ask page so you can opt-in at the time of asking, too.)
Once checked, you will get a single daily summary email of answers to all questions where you've checked this box. You don't even have to visit Stack Overflow to get answers -- as long as you're willing to wait until midnight GMT when the daily rollup email notifications are sent out.
And don't worry -- as with every email we send, there is a one-click global unsubscribe if you don't want to get any more emails from us.