There are a lot of free FTP clients out there for the Mac, but my favorite is Cyberduck. Boasting a great user-interface and support for a wide variety of protocols, it’s a good alternative to the popular but expensive Transmit 3.
The open source software has a number of features that sets it apart from the pack. It works with Amazon’s S3 storage service, supports Growl for system notifications, integrates with a number of editors, and allows for advanced transfer settings using regular expressions. It also has the ability to integrate directly into OS X.
Builds are available for both PowerPC and Intel processors. Popular alternatives to CyberDuck include FileZilla and Classic FTP.
Photo | Cyberduck.ch