phpList
Powerful Open Source Email Marketing app with analytics & segmentation
phpList delivers Open Source email marketing, including analytics, list segmentation, content personalisaton and bounce processing. Extensive technical features and a secure and stable codebase are the result of over 17 years of continuous development.
Used in 95 countries, available in 20+ languages, and used to send 25 billion email campaigns last year.
Deploy it with your own SMTP server, or get a free hosted account at http://phplist.com.