Simple Contacts - Contact lens prescriptions from home
Drupe - Next generation contact manager and dialer.
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 Card Reader - Automagically scan biz cards into LinkedIn/Gmail contacts
GNOME Contacts - All your contacts in one place
Kontact - Kontact is the integrated Personal Information Manager of KDE.