MultiGet is an easy-to-use GUI file downloader for Linux/Unix/BSDs/Windows.
It's programmed by C++ and GUI is based on wxWidgets. It supports http/ftp
protocol which covers most user's requirement. It supports multi-task with
multi-thread on multi-server. It supports resume download if server side have
resume feature, and if you like, you can reconfig the thread number without
stopping the going task. It's also support SOCKS 4, 4a, 5 proxy, ftp proxy,
http proxy.

WWW: http://multiget.sourceforge.net/