Salesforce Data.com - Data.com provides company profiles and contact information across millions of businesses worldwide.
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.
FullContact - Put the power of full contact information into your web or mobile apps.
Drupe - Next generation contact manager and dialer.
HookFeed - Customer Analytics in One Click.
Simple Contacts - Contact lens prescriptions from home