git config --global user.name "Santiago Muñoz"
git config --global user.email santiago@email.com

git config user.name "Santiago M.
git config user.email sm@email.com

https://github.com/jquery/jquery.git

git@github.com:jquery/jquery.git

Host github.com
    HostName github.com
    User git
    IdentityFile ~/.ssh/santiago

git@subdominio.github.com:jquery/jquery.git

Host subdominio.github.com
    HostName github.com
    User git
    IdentityFile ~/.ssh/santiago2