monline

I've not found an up to date list of FTP server software for Mac OS X, so here you go:

• Wing FTP Server
• CrushFTP
• ProFTPD
• Pure-FTPd
• Rumpus
• GoAnywhere Services

PS: note that the above list is not ordered in any way. Eg. the most popular is obviously Pure-FTPd, since it's built into Mac OS X by default.