jClientUpload is a client-side Java component (Applet or WebStart) that allows the user to upload files and folders to a Web or FTP server. It includes features such as a progress bar, FTPS (FTP over SSL) support, the ability to resume broken uploads, a renaming template, and an overwrite policy. The add-ons section includes an image scaling filter, PHP scripting, and a PGP encryption filter.
jftpgw is a proxy server for the FTP protocol. It is highly configurable, allowing you to use an XML-like configuration file to define almost any combination of the client's IP, the server's IP, the user name, the destination port, and so on. jftpgw supports inetd/daemon mode, transparent proxying, forwards, caching, logging, data IP and port specification (port ranges), limiting of the number of simultaeous sessions, and several proxy login styles for clients that support FTP proxies.
JPartialDownloader is a program for downloading files using HTTP[S]/FTP/BitTorrent protocols. It supports many features like resuming unfinished downloads, retrying, and multi-connection HTTP[S]/FTP. What makes this program different from similar programs is that you can download any part of a file.
Junkie is a GTK FTP client. It features support for both IPv6 and IPv4, multiple site connections, a queue for files/directories, a site manager which supports encryption, quick connections, downloading/uploading of whole directories without using the queue, optional caching of directories, editing/viewing of files on the fly, support for playing MP3s (using libjamp), Oggs, XMs, MODs, and more, sound playlist support, and a preferences configuration system.
kio-ftps is an FTPS KIO slave for KDE. It implements secure FTP sessions based on RFC 4217 and built upon the FTP KIO-slave sources. It should work with most server implementations. It issues an "AUTH TLS" command after connecting and refuses to continue when it's not supported. Prior to every data channel I/O command ("STOR", "RETR", etc.) it tries to secure the data channel via "PBSZ" and "PROT" commands. If that fails, it will transfer data unencrypted. There is currently no support for SSL certificates.
KuFtp is a graphical FTP client for the K Desktop Environment. It implements many features required for usable FTP interaction. One of the most notable features is the use of tabs to represent sessions. This is like the feature in Konqueror or Firefox which allows you to have multiple simultaneous FTP sessions in separate tabs. Other features include a bookmark manager, history recording, and a queue manager.
lftp is a sophisticated command line based file transfer program. Supported protocols include FTP, HTTP, SFTP, and FISH. It has a multithreaded design allowing you to issue and execute multiple commands simultaneously or in the background. It also features mirroring capabilities and will reconnect and continue transfers in the event of a disconnection. Also, if you quit the program while transfers are still in progress, it will switch to nohup mode and finish the transfers in the background. Additional protocols supported: FTP over HTTP proxy, HTTPS and FTP over SSL, BitTorrent protocol. IPv6 is fully supported. There are lots of tunable parameters, including rate limitation, number of connections limitation and more.