VLC Media Player - VLC is a free and open source cross-platform multimedia player and framework.
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.
AIMP - AIMP : Free Audio Player : Официальный сайт программы
KeepVid - A free web application that allows you to download videos
foobar2000 - An advanced freeware audio player for the Windows platform.
ShareTube - Watch YouTube, synced with friends.