How to download non-downloadable content with Safari

On some websites you can find movies or audio files which can only be played in the browser but cannot be downloaded. In most cases it is possible to save them on the harddisk because Safari download them in background into the cache. In Safari open the "Window" menu and choose "Activity". A little window pops up which contains a lot of entries with cryptic names and their size at the end of each line. Look for the current website by clicking one of the appropriate triangle. Now scroll downwards and look for an entry of a considerably large size. If you are listening to audio or watching a movie this size can change while the content is downloaded in the background. Either you double click this entry or, if it doesn't download the file, press Apple+C, open the download window and press Apple+V. The link is pasted into the download queue and the file is downloaded. Rename the file later if you want. Sometimes Safari won't download the pasted entry. In this case wait until the file is completely downloaded in the background (check the activity window) and try again.