Most users refuse to provide a valid email address - either because they are in hiding from various Colombian drug cartels (selling Viagra) or the Defence minister of the Nigerian Government who needs assistance getting a fortune out of the country in a hurry on behalf of the Nigerian Royal Family.

Using a fake email is their choice - and obviously no feedback can be provided. If users decide to ask questions in the comments section then it is their responsibility to monitor it for an answer.

Being able to fire emails at one another on the front page will possibly result in 100% of all users providing fake emails when posting comments, or result in users refusing to comment altogether.

Alternatively they could ask the question in the forums and subscribe via "RSS feed for this topic" or edit their profile - to be notified when a "favorite" forum topic is replied to.

It really comes down to using the site as it was designed/intended.

Comments are comments.
Comments are not questions.
Questions and discussion belongs in the forums.
The forums are already able to handle notification of replies either via email or RSS.

Thanks for the suggestion, I can see you mean well - but such a feature would surely be abused by a few to ruin the comments section for everyone.

SUGGESTION: Enter the possibility to address certain former entries. That is, GAOTD sends a notification email to the addressed person. This can easily be automated I believe. You just check an new entry "Notify" and eg "Comment: #33" and then the notification is sent to #33.

Today I found out how to register the PPT-minimizer and would have wanted to notify the poor ones who failed.