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).
phoneutria is a Web crawler that is multi-threaded, scalable, high performance, extensible, and polite. It can be used to crawl, index, load-test, or even download any Web or enterprise domain and is configurable through a XML configuration file. Phoneutria can be used for either checking the links of a Web site or for load-testing purposes (i.e. the level of politeness can be configured). It provides a plug-in mechanism for further extensions.
Jaksta Music Miner for Mac automatically captures and tags MP3s from popular audio and video Web sites. Just open Jaksta Music Miner, play a song or video, and the MP3 is created, usually up to 10x faster than real time. The MP3 can be added to iTunes with the click of one button. It supports Grooveshark, Last.FM, YouTube, Jango, and more and is great for discovering new music or enjoying your music offline.
Xtreme Download Manager is a advanced and powerful tool to increase download speed up to 500%, resume broken/dead downloads, capture FLV videos from any site, and schedule downloads. It uses a sophisticated dynamic segmentation algorithm, data compression, and connection reuse to speed up the download process. It supports HTTP, HTTPS, and FTP protocols, firewalls, proxy servers, file redirects, cookies, authorization, etc. It seamlessly integrates with Firefox on any operating system. It also integrates with any other browser to handle downloads automatically using advanced browser integration. It is entirely written in Java, so it runs on any operating system without even being installed.
Movgrab is a command-line movie downloader for sites like YouTube. It has no dependencies; everything that's needed should be there in the tar.gz package. Movgrab can connect through an HTTP proxy, can output the download to stdout for piping into another program, and can fork into the background to free up the console. When forked into the background, its progress can still be seen in a ps list.
getxbook is a collection of tools to download books from websites. There are tools to download from Google Books' "book preview", Amazon's "look inside the book", and Barnes and Noble's "book viewer". There is an optional GUI written in Tcl/Tk, and some shell scripts using OCR to create plain text or searchable PDFs and DjVu files from the downloaded books.