mailbox synchronization tools

 Sync Mail Dir is a set of utilities to synchronize a pair of mailboxes
 in Maildir format, using SSH to transfer data. It provides the smd-pull
 utility to pull changes made on the remote mailbox, smd-push to propagate
 local changes to the remote mailbox, and smd-loop to iterate push and pull
 in a timely way.
 .
 The software is young and should thus be used with care in production
 environments.
 .
 Unlike OfflineIMAP, it does not require an IMAP server to be installed on the
 remote host. Moreover, it never attempts to automatically resolve conflicts
 between incompatible mailbox statuses - it just notifies the user explaining
 how to fix the problem.
 .
 Sync Mail Dir's design is similar to that of Maildirsync, but is more
 efficient in terms of CPU cycles and disk I/O.