I found a free software called VDownloader that is able to download videos from Youtube, Google, Grinvi and DailyMotion. The difference between this freeware and the rest is that it can save in .AVI, .MPEG and also .PSP! So you don’t need to download and install FLV player and converter.

Easy to use. Just copy the URL from Youtube or other video sites, paste it to the program and click the download button. Once finished downloading, wait for a few seconds for it to convert to the video format that you select from the preferences.

Only 1 thing I don’t like about this software is it doesn’t support a wide range of video sites.
[ Download VDownloader ]
Second method don’t need to use any third party software to download videos. Simply use your favorite web browser, go to VideoDownloader website and enter the video URL.

This website will save your video as .FLV format. So you’ll need FLV player to watch the downloaded videos from Youtube and etc… Good thing about VideoDownloader is it supports a LOT of video sites. 57 of them! Angry Alien, Blennus, Blip.tv, Break.com, Dailymotion, Double Agent, eVideoShare, Free Video Blog, Google Video, Grinvi, iFilm, Keiichi Anime Forever, Metacafe, MySpace, MySpace Video Code, Putfile, Totally Crap, vidiLife, vSocial, AnimeEpisodes.Net, Badjojo, Blastro, Bofunk, Bolt, Castpost, CollegeHumor, Current TV, Dachix, Danerd, DailySixer.com, DevilDucky, Double Agent, EVTV1, FindVideos, Hiphopdeal, Kontraband, Lulu TV, Midis.biz, Music.com, MusicVideoCodes.info, Newgrounds, NothingToxic, PcPlanets, Pixparty, PlsThx, Revver, Sharkle, SmitHappens, StreetFire, That Video Site, VideoCodes4U, VideoCodesWorld, VideoCodeZone, Vimeo, Yikers YouTube and ZippyVideos.
[ Download Videos from VideoDownloader ]
Third and last method is installing a plugin on your Firefox browser. After installing the plugin, you’ll see a small icon on the bottom right of the Firefox browser. Click here to see the plugin in action. This plugin is created by the same person who created VideoDownloader website.
Tip: To watch the videos in .FLV format, you’ll need FLV Player. It’s FREE!

[ Download FLV Player ]