The YouTube downloader allows you to easily download your favorite videos on YouTube.
The videos are stored at the same location the downloader executable is, and they come in the standard YouTube format, which if FLV.
The easiest way to watch FLV files, is to download and install VLC Mediaplayer.
Kep in mind, that YouTube downloader can download any video from YouTube, except those which require you to confirm your birth date.
Get the YouTube Downloader here
What it looks like while downloading.