In his recent blog post Hacking someone's gem with github and gemcutter, Dr Nic shows some improvments to the github gem and how to use them to clone and fork a repository on GitHub in no time. This procedure may speed up the workflow of correcting problems that you discover.
"Ever used a rubygem, found a bug, and just wanted to quickly bust out the big guns and fix it quickly?" - Dr Nic
"A simple tool which helps migrate your locally installed gems from github to gemcutter." - maxim
An introduction to GitHub, which includes how to create new repositories, set up your account, push and pull, clone and send pull requests.
A complete walk through of how to deploy a Rails application straight from GitHub, set up DNS entries and monitor it with New Relic RPM using Webbynode's ReadyStacks.