Go Gmailer is a java based desktop app to send emails.
Source code for be able to use Relation Tags.
A full-featured email creation and transfer class for PHP
a lightweight ANSI C library for handling POP3 mailboxes
Business webmail modular application with mobile client
A simple native java network library
Installation, Configuration, and Automation tool set for Crypt Mining
High volume bulk mailer
This tool helps you to convert many units of calculations.
Quick & dirty RSS-to-email tool
Webmail open-source in php base on Squiremail
Multiple account (or label) Gmail notifier (without storing passwords)
Robust open source POP3 client and MIME parser written in C#
A free .NET library for accessing IMAP servers, written in C#
Provide a Java Mail Provider for Exchange-hosted mailboxes