Retrieve YouTube Videos from your Browser’s Cache

In this episode, we’ll show you how to retrieve previously watched YouTube videos from your browser’s cache. In this episode, we use Window’s XP and the FireFox browser. You can then download YouTube videos and watch them offline using any flash player.

Cached files in Firefox can be found in this Folder:
C:\Documents and Settings\[profile]\Local Settings\Application Data\Mozilla\Firefox\Profiles\[random].default\Cache\

The files are saved with 11 character random names without any file extension. To watch youtube videos rename the cache file as .flv

Better way to view your cache files is to install this FireFox plug-in called Cache viewer:
https://addons.mozilla.org/firefox/2489/
Note: once you install this plug-in the Cache folder no longer exists in the above path

Excellent cross-platform Multimedia Player:
http://www.videolan.org/vlc/