The basic concept is that users register channels where connected viewers can watch videos from different video hosts (e.g., YouTube, Twitch) and the playback is synchronized for all the viewers in the channel.
Each channel has a playlist where users can queue up videos to play, as well as an integrated chatroom for discussion.
The official server is located at https://cytu.be, but there are other public servers hosted for various communities.
Built using node.js, requires MySQL as its back-end.
Baresip is a portable and modular SIP User-Agent with audio and video support. Tries to be a Swiss Army knife for SIP and VoIP. Supports encryption. Has an embedded web server with an HTTP (REST?) API for controlling the utility. Modular architecture.
An extremely high resolution graphics-to-text art utility/library/converter. Aims to be much better than aalib or caca. You can even watch videos rendered into text in realtime. Tries to be cross-platform.
A streaming media server you host yourself. Can run without a container as a first-class implementation (thank you!) Designed with web browsers specifically in mind, not client software. Written in Java, but nobody's perfect (recommends the OpenJRE!)
MoviePy is a Python library for video editing: cutting, concatenations, title insertions, video compositing (a.k.a. non-linear editing), video processing, and creation of custom effects. Use it to convert videos, make animated gifs, add effects....
Personal media server. Kind of like Kodi, but you can use platform specific clients to access your media, just like you can from the television. Streams media as necessary. There's even an HTML5 client so you can use your web browser instead of an app or client. You can use Kodi as a client, too.
Shotcut is a free, open source, cross-platform video editor. Can capture from live media devices (including JACK and PulseAudio) as well as edit media streams. Tries to have a very easy to use UI; UI can be reconfigured to optimize for the kinds of tasks you want to accomplish.
An an easy to use, quick to learn, and surprisingly powerful video editor. Designed to be simple to use yet powerful enough to accomplish some fairly complex tasks. Edit video, edit audio, import images, basic rendered effects. Does background editing and chroma-keying.