While we are still working on Emaily to make it usable for many people, I submitted it to the Wave Samples Gallery, because it can contain some code which would be usable for others, for example usage of guice in a robot and using the "proxyingFor" request field to determine the email address of an email user. The submission is just accepted a couple of minutes ago. Here is the entry for Emaily: http://wave-samples-gallery.appspot.com/about_app?app_id=46003
For people who want to use it: it can send emails, but it cannot receive answer yet. See my previous blog post on the usage.