I think YES. I have not think about solution in detail but it is possible. In my case, I allow user to search answer and post there question via Yahoo messenger / Gtalk / Skype or Facebook chat. Maybe twitter later... haha.
If you use one of chat tools above, you can add:
firstname.lastname@example.org or email@example.com or Skype: ten.kana or www.facebook.com/tenkana
And see around how it works. ( my qa site is http://qa.tenkana.vn