/global-git-ignore

Provides for globally ignored files. Useful when working across many projects.

Mac

git config --global core.excludesfile ~/tools/global-git-ignore/.gitignore

Windows

git config --global core.excludesfile %USERPROFILE%\.gitignore

This will result in an entry in your .gitconfig that looks like this:

[core]
    excludesfile = {path-to-home-dir}/.gitignore

Global .gitignore contents