Mail Direct is a program designed to send emails fastly, safely and directly to recipients, bypassing your ISP's mail server. It's not a mail client but it has a built-in SMTP server which can be quickly setup for use with your favorite mail client.
Mady MTA Service is a small and easy SMTP server. It's small, stable and fast. It can use in a small LAN or home network and provide mail deliver service for a small group of users.
Shareware Assistant is designed to help shareware authors process orders, manage their business, track customer information and offer/ship physical product. It can automatically retrieve order mails from registration services, such as Regnow&Shareit.