Outlook Google Calendar Sync - Offers calendar synchronisation between Outlook and Google, including attendees and reminders.
imapsync - Console-based utility for migrating IMAP mailboxes.
GO Contact Sync Mod - GO Contact Sync Mod is an open source tool to synchronize your Microsoft Outlook contacts with...
Gmvault - Backup the emails in your Gmail account.
gSyncit - gSyncit Outlook Cloud Synchronizer. Outlook Calendar, Contact, Task, Note Synchronizer supporting Google, Toodledo, Evernote, Informant, iCloud, AOL, Yahoo, Synology, Fruux, Memotoo and CalDav/CardDav services.
Cryoserver - Cryoserver is an all-in-one email archiving solution that empowers you to preserve your email in a tamper-evident archive, making you transform your data into a useful archive for everyday use.