From HexNiche System:
mySMTP is a desktop SMTP relay server specially designed to handle huge mail request. It relays all your mails to their recipients directly without going through any ISP's mail server. Key Features: Ultra-fast multithreaded mail deliver engine; Reliable queue system, no more worry about PC hang, will resume sending from the mail it stopped. Unsuccessful mail will be retried 48 times by default, we ensure message conveyed if the recipient's e-mail is valid. By using external proxy servers, able to hide your IP address in order to protect your online privacy. Inbuilt MX record cache to reduce waiting time; configurable listened IP and port, allows co-exist with other SMTP servers; allows unlimited size of mail body, attachments, and recipients in a single mail; detailed log file.