Kodi - Kodi is an award winning free and open source media player that got its start on the Xbox console.
Sonos One - A self-contained, Alexa-connected speaker from Sonos
Emby - media server for personal streaming movies tv music photos in mobile app or browser for all devices android iOS windows phone appletv androidtv smarttv and dlna.
PHOTIVE SPHERE - Affordable bluetooth speaker with built-in stand
Universal Media Server - Universal Media Server allows you to host your entire library of video, music, and pictures, and broadcast them conveniently to a wide variety of different devices.
Amazon Tap - Amazon Tap is a portable Bluetooth and Wi-Fi speaker. Just tap the microphone button and ask for music, hear news, search for information, order a pizza, and more with the Alexa Voice Service.