While working through the freeCodeCamp curriculum, I had to complete a project using web sockets. For that project, I built an application where you could search for a stock ticker symbol and it would chart the last 100 days of activity on the stock market. It used websockets to update any clients that might be listening for changes on the server. You can see that project, here.
I chose to use socket.io to complete that project and found it simple and enjoyable to work with. I put together this talk to give at the BellevueJS meetup group in September 2017 to show attendees how easy it was to get started with web sockets.