ASynK - Awesome SynK
PIM Sync Done Right.

Introduction

ASynK is a flexible Contacts synchronization program that works with a variety of Contacts software such as Microsoft Outlook, Google Contacts, and Emacs BBDB.

Some of the key features of ASynK are:

  1. ASynK allows two-way sync of Contacts across any two supported sources - Google Contacts, Microsoft Outlook, CardDAV and Emacs BBDB.
  2. ASynK is the only two-way synchronization option for BBDB known to be in existence today. So if you are keen to keep your BBDB content synchronized with a mobile device or Outlook, look no further.
  3. ASynK works on Windows, MacOS X, and Linux. Outlook synchronization only works on Windows.
  4. Synchronization is granular to the level of 'Folders', i.e. you can synchronize one folder of Google Contacts with a Outlook folder (on Windows at work, say), and another Google folder in the same account with BBDB (On your Mac, say)
  5. The infrastructure is there to add more database and item types (i.e. tasks, notes, etc.), but currently only Contacts synchronization for Google Contacts, BBDB and Outlook supported
  6. It is free software, and released under the GNU AGPL (Affero GPL) version 3