segmentio/analytics.js — pull request #359 by jpiasetz (2014-04-02 13:28:21+00:00)
Title: Set 0.0.0.0 to also be localhost

Analytics.js doesn't save a session cookie when the page is served from 0.0.0.0. Yeoman's webapp generators default Gruntfile.js suggests using 0.0.0.0 instead of localhost when you want to share from your comptuer so I imagine this is fairly common (https://github.com/yeoman/generator-webapp/blob/master/app/templates/Gruntfile.js#L85). A better fix would be to make it handle ip in a more robust way.