The call Serena Button was a weekend hack project that I built during my summer internship at ChallengePost as a HackNY Fellow. ChallengePost has some remote employees and after our awesome developer evengelist, Neal, built a chrome extension to open hangouts with our remote employees I got the idea to bring this extension into the physical world with the help of an Arduino, Chrome Packaged App, 100mm Arcade button, and a few late nights.
Essentially, the chrome packaged app just runs on the user's computer and listens for any data getting sent over a connected serial port (in our case USB) and when it receives data from the Arduino, which sends data when the button is pressed and circuit completed, it opens up a google hangout with CP's project manager, Serena.
Playing with Arduinos is always fun, but I also used this as a project to learn more about developing Chrome's Packaged Apps. I have since ported it to a Node.js app running locally since it is much more flexible, but the Packaged App makes it much simpler to distribute to people who don't already have an Node environment configured on their machine.
For a full blogpost on this you can check out: http://blog.challengepost.com/post/93328687487/hacking-the-office-arduinos-extensions-and-hangouts