Aerc is an email client that runs in your terminal.  It is highly
efficient and extensible, perfect for the discerning hacker.

Some of its more interesting features include:

- Editing emails in an embedded terminal tmux-style, allowing you
  to check on incoming emails and reference other threads while you
  compose your replies
- Render HTML emails with an interactive terminal web browser,
  highlight patches with diffs, and browse with an embedded less
  session
- Vim-style keybindings and ex-command system, allowing for powerful
  automation at a single keystroke
- First-class support for working with git & email
- Open a new tab with a terminal emulator and a shell running for
  easy access to nearby git repos for parallel work
- Support for multiple accounts, with support for IMAP, Maildir, SMTP,
  and sendmail transfer protocols
- CalDAV and CardDAV support for synchronizing contacts & calendar
  events
- Asynchronous IMAP support ensures the UI never gets locked up by
  a flaky network, as mutt often does
- Efficient network usage - aerc only downloads the information
  which is necessary to present the UI, making for a snappy and
  bandwidth-efficient experience

WWW: https://aerc-mail.org/