Sftp
filezilla-project.org
FileZilla - The free FTP solution for both client and server. Filezilla is open source software distributed free of charge.
12,789 
$ 1,049,760.00
mobatek.net
Home of MobaXterm X server and SSH client, MobaSSH SSH server, MobaLiveCD, MobaPhoto and MobaMotiv
35,331 $ 380,160.00
chilkatsoft.com
Chilkat Software: Cross-Platform/Cross-Language API's for SSH/SFTP, FTP, Email, Encryption, Zip, S/MIME, XML, EML, MHT, FTP, SSL, TLS, and more
168,040 $ 66,000.00