Cyberduck is one of popular open source and free FTP, SFTP, WebDAV, Cloud Files and Amazon S3 browser for the Mac OS X. This software is written by David V. Kocher. The program has simple and easy to use with quickly accessible bookmarks. You can limit the number of concurrent transfers and filter files using a regular expression. And you can also resume both interrupted download and uploads.
Here are more highlight features:
- FTP, SFTP, WebDAV, Cloud Files and Amazon S3 browser.
- Available in over 20 languages.
- Synchronize local with remote directories.
- Modify permissions on multiple files and recursively.
- Supports Public key authentication, Keyboard Interactive (PAM) Authentication.
- Quick Access bookmarking.
- Integration with external editors.
- First Class bookmarking
- Manage Google Docs
- Amazon S3
The program supports multiple languages including English, Czech, Dutch, Finnish, French, German, Italian, Japanese, Korean, Norwegian, Portuguese, Slovak, Spanish, Chinese Traditional and Simplified, Russian, Swedish, Hungarian, Danish, Polish, Indonesian, Catalan, Welsh, Thai, Turkish and Hebrew. You can enjoy using it with your own language.

