Over one weekend, I joined my friends and colleages Helen Zeng and Timothy Strimple in Los Angeles to compete in the infamous Node Knockout hackathon. We built a tiny HTML5/Canvas shooter with Melon.js that has multiplayer powered by Node.js and Socket.io. We used a bunch of Creative Commons-licensed art and coded our way to a quick, easy and fun shooter for Node Knockout 2013. You can check out our quick pitch video (which also shows the game).
We released a version that has been cleaned up for people who'd like to get a jumpstart on building a similar game. Feel free to use it to build your own game, but please understand that we used art found online, so please respect their individiual licenses. I spent some time to comment most of the code, so it should be pretty easy for people to understand what we've done there. You can find the package on GitHub.
Like the effort? Please vote for us! Visit the game site on Node Knockout and click the "Vote" button at the bottom of the page!