Windows command line emailer

SendEmail is a lightweight, command line SMTP email client. If you have the need to send email from a command line, this free program is perfect: simple to use and feature rich. It was designed to be used in bash scripts, batch files, Perl programs and web sites, but is quite adaptable and will likely meet your requirements

msmtp is a really good command line SMTP client. I've been using it for quite a long time. For more information, read the manual.

Bmail is a free but lean command line SMTP mail sender.

C:\>bmail -s mars -t cpeacock@max -f root@neptune -h -a "Data Download Script
is not Working Correctly" -b "The script on neptune has stopped getting data"

Command Line SMTP Emailer V1.07
Copyright(C) 2002-2004 [email protected]
Opening connection to mars [192.168.0.10] on port 25
220 mars ESMTP Postfix (Release-20010228)
250 Ok: queued as 04168186A7