Simple bash-script allowing pair to be identified on git commits:

$ git pair "Nelson Senna"

From now on, your commits will be identified with authors like:

commit a101286e02117fdafea58742074694138d578948
Author: Augusto Pascutti + Nelson Senna <augusto@phpsp.org.br>
Date:   Thu Sep 3 23:00:58 2015 -0300

You can use as many pairs you want, all you need is keep issuing commands to add more authors.

git pair ended

At the end of your pairing session, the above command will reset author names to your global user.name configuration on Git.

One-liner using Sinister:

$ sh <(curl -sSL http://git.io/sinister) --local --url https://git.io/git-pair

Or you can clone the project where you want to, all you need after is to sym-link the git-pair script to your $PATH:

$ cd <my-src-dir>
$ git clone http://github.com/augustohp/git-pair
$ chmod a+x git-pair/git-pair
$ ln -s <my-src-dir>/git-pair /usr/local/bin

Now you should be able to execute git pair anywhere.