Safari comes with an incredibly powerful tool called the “Activity” window, which can be used to download YouTube (or any other video site) videos, files from websites, MP3s from Last.fm or any other type of file present that can’t be directly downloaded, right to your desktop. There are many third party applications and services that allow users to download YouTube videos directly, but many people do not realize that this functionality is built right into Safari.

To illustrate this, I’m going to use YouTube videos as an example (.flv file format), but as stated previously this works with any online file.

Simply go to the YouTube video page where the video plays, click Window -> Activity and a window will appear similar to the one pictured below.

We’re shown a range of different files in this list, but we’re looking for the flv video file, which will most likely be the largest file of the list (highlighted below).

Select that file, hit copy and paste it into the Downloads window (Window -> Downloads), and the video will start downloading to your desktop. Note: With YouTube videos, the downloaded file will be called “get_video” with no file extension, you’ll need to rename it to “something.flv”, in order to be able to play it.