VLC is a free and open source cross-platform multimedia player and framework that plays most multimedia files
Smplayer
SMPlayer is a free media player with built-in codecs that can play virtually all video and audio formats.
Qoob
Simple music player.
Webtorrent
App to connects to both BitTorrent and WebTorrent peers and even play the files before downloading.
Lollypop
Lollypop is a new GNOME music playing application.
CPod
Podcast application for Linux.
Cozy
Cozy is a modern audiobook player for Linux and macOS.
Cantata
A simple music player.
Oras ng Popcorn
Popcorn Time streams free movies and TV shows from torrents.
LibrengTube
FreeTube is an open source desktop YouTube player built with privacy in mind.