A browser developed by SRWare based on source code of Chromium. Homepage: http://www.srware.net/software_srware_iron.php
Main difference to Chrome is the data privacy. SRWare claims not to transmit some user related data to the server. The user tracking (or browser instance tracking) is removed from the source code.
However, don't think you are anonymous, if you use IronBrowser. No one uses naked browser, because everyone likes the one or the other plugin, be it ad-blocker, session manager or other fancy things. These plugins have access to the browsing history and some user related data. And if these plugins don't care about your privacy, they don't care about your privacy...
Not really related to the browser itself, but since it's about privacy: http://panopticlick.eff.org/ There is also a paper on this site about how anonymous our browsers are.