ContactRescue - Magically get your address book up-to-date and accurate
Cardhop - The Mac contacts app you'll want to use.
Webby - Webby allows to use Facebook, Youtube or any web app as a regular desktop apps, integrated with the...
Clearbit Connect - Clearbit Connect is a free extension that surfaces actionable information on the people who email you.
NetHunt CRM - Turn Gmail into a smart CRM
Wall Of Me - Wall of me: all your favorite socials in a single place.