Sylpheed 3.6 Description by the Software Developer:
"Sylpheed is a simple, lightweight but featureful, and easy-to-use e-mail client (mailer, MUA). Sylpheed runs on Unix-like systems such as Linux, BSD, and Mac OS X.
- Simple, beautiful, and well-polished user interface
- Comfortable operationality which is built in detail
- Immediately available with minimal configuration
- Lightweight operation
- High reliability
- Internationalization and Multilingualization support
- High-level Japanese processing
- Various protocols support
- Security features (GnuPG, SSL/TLSv1)
- Powerful filtering and search
- Junk mail control
- Flexible cooperation with external commands."