Download Youtube Videos With Easy Tricks

There r several ways to download a youtube videos.if ur using firefox there is a plugin to grab videos from youtube.using orbit downloader ,internet download manager ,flash get all the download mangers mostly having the options to grab FLV videos.I am mostly using orbit downloader for grabbing flv videos.
the another easy ways i heared before 1 year is renaming the url of youtube videos.suppose if ur youtube url is like this

http://www.youtube.com/watch?v=xxxxxxxx

Just renaming this url will redirect you to a download page .rename the word youtube in the url to voobys.(eg)like this

http://www.voobys.com/watch?v=xxxxxxxx

After Downloading the file rename the file to filename.flv
Now the another trick for url is there using only ok keyword.
that is very simple to use.
in this way just adding ok befor the word youtube in the url for (ex) just like this

http://www.okyoutube.com/watch?v=xxxxxxxx

i think changing the url is better than using grabbers and other tricks.especially using ok keyword is better.