GFTPD
- Full featured FTP server with SSL/TLS support for Linux.
- http://modeemi.cs.tut.fi/~jonni/gftpd/

Jscape
- Platform independent FTP server with support for FTP/S and HTTP/S protocols.
- http://www.jscape.com/secureftpserver/

Troll Tech FTP Daemon
- The FTPD FTP Daemon is a random hack, not a product. It no longer actively maintained by Trolltech, but is offered free of charge, in the hope that it may be useful
- http://www.trolltech.com/developer/downloads/qt/freebies

WuFTP
- Washington University FTP server, was one of the most public used Unix FTP Daemons.
- http://www.wu-ftpd.org/

vsftpd
- The "Very Secure FTPD" is a *nix (Unix, Linux) FTP Server. Used by ftp.kernel.org
- http://vsftpd.beasts.org/

Small, portable and efficient FTP server.
- Small, portable and efficient FTP server, with online administration and many security features.
- http://www.wzdftpd.net

ProFTPD
- Designed from the ground up for security, configurability and ease of administration.
- http://www.proftpd.org/

NcFTPd
- Designed especially for high-traffic sites and internet service providers.
- http://www.ncftp.com/ncftpd/

glFTPd
- This is a full-featured free FTP server for *nix systems with intergrated administrative and statistics features.
- http://www.glftpd.com