Once you have many people asking you the same question, it's natural to start thinking of making a FAQ page, but this is a different idea to streamline the process:
When we read and write our e-mails, we already have special symbols (such as ">") allowing to indicate fragments of text to which we
are responding to. Gmail could thus recognize such blocks of texts as blocks of Q&A, and add hover-appear check-boxes near each such block, allowing one to select which blocks to include in the public profile.
After doing so, the e-mails that have at least one of the blocks checked, would appear in the "Profile" category, with special "reedit" and "publish" rights, where you could reedit these answers and all aspects of the e-mails without losing the originals, reorganize the Q&A blocks by easily moving the blocks across the e-mails in the "Profile" category, and publish by clicking "Publish".
After publishing, the e-mails would appear on http://gmail.com/username, searchable, and in the same style as usual Gmail's interface, so that people could read, search or even reply to these e-mails (with or even without signing-in).
Having many questions answered at a particular username's namespace would constitute a public Gmail profile useful for more efficient mass communication.