Global .gitignore for IDE specific exclusions

I work in a team with disperate IDEs. So, when we start a new project, each of us ends up adding our IDE specifics to the project’s .gitignore; e.g. for WebStorm, RubyMine:

.idea/

For sublime text 2:

/*.sublime-project
*.sublime-workspace

Not a big deal, but a bit tiresome. I also found myself adding these as step 1 of submitting a PR to an OSS project. This is bad because it muddies the .gitignore. Thankfully, on a  recent PR a maintainer clued me into global gitignore. Read up on them on github. But it works just like you’d imagine, I can add my IDE specific excludes to my global gitignore and never have to muddy another project’s .gitignore again.