Great Downloader easy to use can convert into multiple file formats. Fast and impressive
KeepVid - A free web application that allows you to download videos
Video DownloadHelper - Browser extension to download videos from the Web
YoutubeMultiDownloader - Just like its name YouTube Multi Downloader, it is an online website for downloading the videos of downloading without using any video download and accelerator.
youtube-dl-gui - A cross platform front-end GUI of the popular youtube-dl written in wxPython.
SaveFrom.Biz - Convert YouTube video URL to MP4 file and download it to your device. SafeFrom is the best YouTube video downloader and converter.
Youtube Video and Audio Downloader - Download YouTube videos in all available formats and extract the original audio files.