mutt — Command-line email client. More information: <http://mutt.org/doc/mutt.1.txt>.

Open the specified mailbox

mutt -f {{mailbox}}

Send an email and specify a subject and a cc recipient

mutt -s {{subject}} -c {{cc@example.com}} {{recipient@example.com}}

Send an email with files attached

mutt -a {{file1 file2 ...}} -- {{recipient@example.com}}

Specify a file to include as the message body

mutt -i {{path/to/file}} {{recipient@example.com}}

Specify a draft file containing the header and the body of the message, in RFC 5322 format

mutt -H {{path/to/file}} {{recipient@example.com}}