Softabar Command Line Email Client 

Softabar Command Line Email Client is a tool for email automation. Use this tool to send, receive and monitor email, directories and files from a command line and from scripts.
softabar command line email email command line softabar

febooti Command line email 

Utility to send email from command prompt; send attached files, plain text or HTML (with embedded pictures). Supported - TO, CC (Carbon Copy), BCC (Blind Carbon Copy), alternate text for email programs that do not support HTML messages, text encoding
command line mail command line mailer command line e-mailer command line smtp scheduled email send email command line html email html mail automatically send e mail

CliMail 

CliMail is a set of command line utilities designed to send and receive email. Send plain-text or HTML (with embedded pictures) email with attachments using to, bcc, and cc recipients. List, display or delete email from POP3(S) or IMAP(S) mailboxes
smtp pop3 imap smtps pop3s imaps secure email email attachment