I use and love gmail. However, since i use email for customer support, I'm always doing a cross reference lookup via the search feature to see my past conversations with the person whose email I'm reading.

I'd love to have a right sidebar widget that shows me, for any email I choose to read, the list of previous conversations/emails with that person.

Is this possible? I'm using Chrome

Ideally, this sidebar would bump or replace the contextual ads that now display over there.