I love sharing youtube videos with my friends, and usually, the fastest way to do so is using instant messaging. But chances are, your links will get lost in the cluster of messages. But we eliminate that. PartySync is simple. You create a playlist name, send it to your friends, and they can add their favourite youtube videos and collaborate.
Or if you're going to a party, you can add music videos to a playlist and it plays automatically on a host computer. Anyone with a laptop or smart phone can download the app and with a simple playlist ID can contribute to the music!