GNU Wget is a free software package for retrieving files using HTTP(S) and FTP, the most widely-used Internet protocols. It is a non-interactive command line tool, so it may easily be called from scripts, cron jobs, terminals without X-Windows support, etc.
TubeMaster++ is a powerful tool which can capture multimedia files you are watching or listening from your internet browser (FLV,MP3,MP4). Captured files can be saved directly on your computer or converted to other popular video or audio formats (AVI, MPEG, MP3, MP4, IPod, PSP ..Discontinued
The project seems to be no longer maintained and the official website is no longer available. The last version, v2.7, can be still downloaded from Softpedia and the source code is available on SourceForge (v2.5).
KGet is a versatile and user-friendly download manager for KDE. By default it is the download manager used for Konqueror, but can also be used with Mozilla Firefox. KGet is part of the KDE Network package and can download files from FTP, HTTP(S) and BitTorrent sources.
Progressive Downloader is a free download manager for your Mac that supports multi-thread downloading and mirror search. It's also capable to download files from the most popular file hosting services.
VisualWget is a download manager that use Wget as a core retriever to retrieve files from the web. You can think of VisualWget as a GUI front-end for Wget that give you all of Wget functionalities (e.g.Discontinued
The program is no longer updated. Last version, 2.5a2, released in May 2012, can be still downloaded from the official website.
Steadyflow is a GTK+ based download manager that aims for minimalism, ease of use, and a clean, malleable codebase. It should be easy to control, whether from the GUI, command line, or D-Bus.
The project is no longer developed. Last version, 0.2.0, released in June 2012, can be still downloaded from Launchpad.