How do you download youtube videos onto your computer? Do you use those web sites to do it?
There is a smarter way of doing it.
The clive command. It is available for Linux. Not sure about windows.
If you are on ubuntu life is easier... 'sudo apt-get install clive' will install clive.
downloading a video is as easy as typing the command,
$clive 'http://www.youtube.com/watch?v=sOpCfIRA9MY'
Do quote the url, it may have special characters that the shell interprets.
Read the man page for more details.
The feature that I liked is the ability to download multiple videos....
put all video links in a file, ex: videos.list then,
$cat videos.list | clive