DownThemAll download manager

Download accelerator and manager DownThemAll gives a swift kick in the pants to Firefox's download manager, providing the browser not only with heightened downloading chops, but with an effective tool for sniffing out media content on Web pages and getting it on your hard drive quickly.
New in version 2 are some sweet tools for making it all happen faster. While support for Firefox 4 was essential to the add-on's continued life, the granular controls over download speeds are a welcome surprise. You can now set different maximum download speeds by individual download, by server, or as a global preference. Separately, you can also set download limits by server.
Firefox's trackless browsing option receives support in DownThemAll 2. This means that even if you're running in Private Browsing mode, you can run the add-on and get the increased download speeds it provides.
The media-sniffing option will discover and download audio and video embedded or linked in a Web page for you, as long as you're looking at a site on HTTP or HTTPS. Of course, this is the case for the vast majority of users and ought not to pose a problem.

Download link

Download DownThemAll download manager here