TrueDownloader is an open source download manager/accelerator with good features like Pause/Resume downloads, simultaneous downloads, segmented downloads for acceleration. Both HTTP and FTP protocols are supported , and its very fast ! You can even improve it or adapt it to your needs since its open-source. Some special features like HTTP/FTP Proxy support and ZIP previewing are supported too. Integrated flawlessly into Internet Explorer, Mozilla and FireFox thanks to the Extension Technology.