Thunderbird

Add-Ons

British English Dictionary

https://addons.mozilla.org/en-US/thunderbird/addon/3366

Lightning

https://addons.mozilla.org/en-US/thunderbird/addon/2313 Calendar

Synkolab

Sync's Contacts, Calendar and Tasks with IMAP folder

Zinidus

Sync's Contacts with Google

• To sync with Blackberry (via Google)

Provider for Google Calendar

Sync's Calendars with Google

• To allow writing to Google hosted calendar
• To sync with Blackberry (via Google)