Caffeine driven bursts of non-stop programming are the best way to spend weekends; the competing teams are icing on the cake. Till now, I've taken part in a bunch of hackathons online, offline, programming, competitive coding and Capture The Flags.
OpenSource hobbyist,
Google Summer of Code
working on Fedora Gooey Karma
Xamarin Intern.
Built a Crossplatform application with the server for same using Xamarin and C# respectively