notmuch
mutt-wizard is a tool that automatically sets up a NeoMutt-based minimal
email system.
It configures mutt and isync with a default interface and safe passwords.
muchsync synchronizes notmuch mail across machines.
muchsync brings notmuch to all of your computers by synchronizing your mail
messages and notmuch tags across machines.
The protocol uses pipelines to work efficiently over high-latency networks
such as mobile broadband.
Lieer is a fast email-fetching, sending,
and two-way tag synchronization between notmuch and GMail.
This program can pull, and send, email and labels (and changes to labels)
from your GMail account and store them locally in a maildir with the labels
synchronized with a notmuch database.
The changes to tags in the notmuch database may be pushed back remotely to
the GMail account.