Interarchy
From Applepedia
Interarchy is one of the oldest FTP_clients on the Mac, with only Fetch having been around longer. (To be technical, BSD ftp is probably the oldest FTP client on the Mac now.)
Interarchy has been enhanced continuously over the years as is the most powerful client available, including not just basic transfer functionality, and the mirroring and scheduling features that are reasonably common these days, but also including powerful networking tools, full AppleScript support including recordability, checking or downloading web sites, as well as list, column and icon views.
Of course, this power comes at a price, Interarchy is both the most expensive of the FTP clients, and generally takes the most time to learn, although its Finder/Safari like windows allow a reasonably easy transfer of skills, especially if you are not after the simplistic side-by-side "Font/DA Mover" style interface.
