FlashGot is the free add-on for Firefox and Thunderbird, meant to handle single and massive (“all” and “selection”) downloads with several external Download Managers.

µTorrent is an efficient and feature rich BitTorrent client for Windows sporting a very small footprint. Most of the features present in other BitTorrent clients are present in µTorrent, including bandwidth prioritization, scheduling, RSS auto-downloading and Mainline DHT (compatible with BitComet).

FrostWire, a Gnutella Peer-to-Peer client, is a collaborative effort from many Open Source and freelance developers located from all around the world.

DownThemAll is all you can desire from a download manager: it features an advanced accelerator that increases speed up to 400%, it allows you to pause and resume downloads at any time and, last but not least, it´s fully integrated into your favorite browser!