Here's a cool site I found yesterday. They have no description I can copy here, but it's not hard to use. You enter the link to a file you want to download (or YouTube video), click on "Download", and they fetch it for you. In the case of YT links, you can choose between regular or high quality. They have a Firefox addon.
It could come useful to break through firewalls or as a video downloader, although for the last one there are better alternatives. You must have JavaScript enabled for it to work.
YouTube to ZIP Service - Zipped
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