Just noticed that GitHub introduced a cool feature: you can edit your files in place on GitHub page. Don’t know how long has this been available but I discovered it just today. When you navigate to a file you have write access to, you will notice an “edit” link right above it. Click it, edit the file, add a commit comment and you’re done.
For me this is a great feature because no matter how many times I review READMEs etc. before committing, there will always remain some typos that I notice only after pushing the file to GitHub. Also useful when you’re away from your computer and have to modify some file but don’t have time or possibility to fetch the whole repo from GitHub.