Clearbit Connect - Clearbit Connect is a free extension that surfaces actionable information on the people who email you.
Google Contacts - Google Contacts is Google's contact management tool that is available in its free email service Gmail, as a standalone service, and as a part of Google's business-oriented suite of web apps Google Apps.
ZoomInfo - ZoomInfo is a B2B database providing detailed business information on people and companies.
Drupe - Next generation contact manager and dialer.
Ampliz Sales Buddy - Data to power your business
Simple Contacts - Contact lens prescriptions from home