Need a Cross-Platform Download Manager ? Take a look at MultiGet multithreaded download manager. MultiGet can be installed on Linux, Windows, BSDs and MacOs. It supports HTTP/FTP protocols which covers the requirements of most users. It supports multi-task with multi-thread on multi-server. It supports resuming downloads if the Web server supports it, and if you like, you can reconfigure the thread number without stopping the current task.
Binaries for Linux and Windows Operating Systems are provided along with the source code at File Download Page.