GoogleTube is a Firefox extension that lets you view YouTube videos directly from the Google Search screen.
Whenever you do a search on Google, GoogleTube will mark any results that point to YouTube videos with an icon that takes you directly to the video. You can then download it in FLV or expand the information without searching the page.
You can choose the size of the player window as well as the background color can change.
It is very easy if you want to avoid searching on YouTube, which is not always the most reliable. This is one of the fastest ways to download videos on your computer.