Minitube!

NewPipe is a lightweight YouTube front-end for Android.

SkyTube is an ad-free, open-source YouTube app for the Android platform. Features: browse popular/trending videos, subscribe to YouTube channels, play videos and more.

Echoes is a YouTube media player that provides a great, simplified user experience with no trailer ads or other distractions like comments. Simply select a video to play it and add it to a live playlist with an easy option to go full screen. Easily interact with playlists and login through Google+ to access your playlists from YouTube.

Kaku is the next generation music player supports many different platform like YouTube, Vimeo ... etc. With it, you can listen to any music you like in different platform with just one single click, so simple to use !

Cherryplayer is a free Windows multimedia player that streams millions of music files from VK.com, plays most multimedia files and includes a superior YouTube player and download service.

ProTube is a full-featured video player for YouTube.

Free Youtube browser for SMPlayer which allows to browse, search and play YouTube videos. No flash needed!

A lightweight application for searching and streaming videos from YouTube.

myTube is a YouTube app built to keep your video playing no matter what. By lightly fading the video into the background, you can continue to watch while you read comments, browse channels and videos, and everything else you can do in the app. If you can do something in the app, then you can do it while watching a video!

quietube is the distraction-free way to watch videos on the web. Watch videos without distractions like comments or ads. It supports YouTube, Vimeo and Viddler.

YouTube Movie Player for Mac OS X.There is no better place to find movies than on the YouTube website, but did you ever want to play YouTube movies outside of your web browser in a sophisticated way right on your screen.

Play YouTube video continuously with playlists.

Elmedia is a free media player for Mac that supports various video and audio formats, including FLV, SWF, MP4, AVI, MOV, MP4, DAT, MP3, etc. The app features built-in web browser that allows you to watch online videos directly from the app, while Open Online Video lets you to do it without noisy ads. There is plenty Elmedia offers to enhance your viewing experience: 10-band equalizer to shape your audio tone, video aspect ratio change to fit image into screen, optimize your video viewing by adjusting playback speed,on-screen display for actions such as pausing, playback. Add hardware accelerated decoding to the list. It can significantly unload the processor, helps avoiding video slowdown, helps with sound to video sync, etc. Elmedia can play video in full screen mode or pin player window on top of other running apps so you do not miss a moment of a movie. The player has its own volume control, enables you to edit subtitles, and more. »

The video browser for motion freedom, MotionBox is a desktop client for streaming video that lets you stream videos from YouTube, Vimeo and Dailymotion.

With VinnPlayer you can play, listen to and save your favorite YouTube video's in an easy to use interface. Now you don't have to download mp3's and use other software to listen to your music. YouTube stores a lot of music video's for you free to listen to.