Ok, here is what we gotta do :
First , Clear the Firefox cache. This would help you to find files easily.
Click on Clear Private data Now making sure that you put a check next to cache.
Navigate to your favorite website that contains the flash animation / video. Let it load fully. Specially if you are on youtube make sure that the movie loads fully. Once that is done type the following (without quotes) “about:cache”
in the address bar of Firefox to get the following page.
Select your file , do not try to save anything from here. Wait … the fun has just started…. Simply Click on the desired file to get the following screen
Now , right click on teh desired file and click on Save Link As. Do not put any file extension , just save it as teh desired extension would be picked up automatically after the file is saved. You are done!!!
Please put some comments if this has helped you..