http://power-video-downloader.en.softonic.com/
Power Video Downloader is a good one as well.

ah, now I saw that http://free-youtube-download.en.softonic.com/ is a good option as well.

atube catcher is a very good option

lots of youtube-downloaders allow U to download files from all video sites. You can make a Q with all Urls u want 2 download and watchem l8r,u can use firefox-addons too: http://onsoftware.en.softonic.com/youtube-downloads-the-best-add-ons-for-firefox

Well, you can have a try on my answer :-

realplayer or IDM

If you use the Opera web browser, try this addon: https://addons.opera.com/en/addons/extensions/details/fastesttube-youtube-video-downloader/1.5.4/?display=en

This is a free ADDON for Fire fox & IE Explorer both and very good freeware ANT Video Downloader

Internet Download Manager, Tube Hunter,
Orbit Download Manager, are also work fine
I m using IDM to hunt TUBE VIDEOS

if you go to www.download.com and type in youtube downloader all software related to your search query will come up, and you can browse through and choose the program that you think will benefit you the most.

There's many ways. You can go to freemake.com and get their video downloader. It also comes with optional firefox and chrome extensions. However, there are also browser addons depending on which one you have.
Firefox: DownloadHelper. This is my favorite
Chrome: I'm sure there are many, but I do it the old fashioned way. Go to the page your video is on and type Ctrl + U. Then type Ctrl + F and type "swf" into the find box. Go through those, and you'll find your video (Right-click 'Save link as'
Opera: The new release finally supports extensions, so it's still up and coming.