Downloadermac is a Cocoa application for downloading items from the Internet. It frees up your browser for other tasks by reducing the load on your Web browser's process by creating a thread just for downloading items.(e.g. firefox-bin, safari). It is tested on both Panther (10.3.9) and Leopard (10.5).
HeldenViewer makes it possible to search for, download, and view Youtube videos in a very easy to use fashion. An important feature is the concept of adding authors as favorites, in order to be notified at the next start of HeldenViewer if the author has uploaded a new video. You will no longer be interrupted by any commercials. Much like the Youtube platform, you can watch the videos while downloading and use your favorite videoplayer to do this. The only restriction is that the video player must be able to play .flv files, e.g. VideoLanClient.
MuDownManager is a program for managing downloads from Megaupload and Rapidshare for premium members. It is lightweight and cross-platform. Downloads can be started in a batch by specifying a list of URLs. Links can be copied directly from your preferred Web browser and pasted into MuDownManager. MuDownManager lets you skip LinkBucks. It has a very simple and intuitive GUI. It is pluggable, allowing support for other download sites to be added in the future.