Are you familiar with
aria2? It's a flexible open source utility for downloading files that supports numerous protocols, including HTTP(S), FTP, BitTorrent, Metalink and more. It has a number of unique features, including the ability to download files from multiple sources, and you can stop and then resume downloads. We caught up with Tatsuhiro Tsujikawa, administrator and lead developer, and asked him about the application and his thoughts on open source.