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.
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.
Elmedia Player PRO makes it easy to download videos from online sources such as YouTube, Vimeo, DailyMotion, Metacafe, and many others. Using it is just a matter of entering the link to the page with your desired video in Elmedia Player and choosing the content you want to download from the list. When you are downloading SWF files, you are given the option to preview all external resources used by the SWF animation. You can download them along with the SWF file if you wish, or even download just the external resources without the initial SWF. Other features include full-screen mode, "Always on top" mode, the ability to make screenshots of your favorite movie moments, and the ability to convert the whole movie into a series of images.