Signed up for Hacktoberfest again this year. It's good stuff. Last year, I got a free shirt after submitting some pull requests for my TacoBot Twitter Bot. It was pretty cool. I haven't kept up with poor TacoBot, but he's still kind of around doing his thing.
Check out out: Hacktoberfest.
The idea is to help the open source community grow by encouraging people to submit pull requests and contribute to projects.
Definitely give it a go!