It'd be nice to have a Gmail agent. The most useful event would be receiving an email, but conceivably, sending an email could also be useful. The payload would include the label hierarchy and star status along with all the other typical email fields (from, to, cc, bcc, subject, body, attachments[?]). These could then be passed along to the TriggerAgent to do all sorts of useful things.

Paired with Google Voice, this could also allow for hacky SMS integration (which I'd really like).