Here's an interesting concept: A variant of Chrome re-branded by security software outfit Comodo as a safe-browsing tool. Comodo Dragon, as it's called, is functionally identical to Chrome, but it sports a slightly reworked interface and a few security-related changes under the hood.
On installing Dragon, one of the options you're given is to use Comodo's own Secure DNS servers, either with Dragon alone or for your entire system. This feature, Secure DNS, automatically blocks access to websites that have been flagged as untrustworthy by Comodo's threat-detection network. You can toggle it back off if it creates more problems than it solves. (I ran into no issues myself.)
You can also elect to set up Dragon in a "portable" installation, where the program's executables and options are all stored in a single directory -- handy if you're using PortableApps or some other self-contained app solution, or if you want to try out Dragon side-by-side with an existing browser.
Cosmetically, Dragon resembles Chrome, but a few key changes have been implemented. Dragon's wrench menu is accessed by clicking the icon at the upper left-hand corner of the window. In place of the wrench menu is a quick link to Comodo's Site Inspector service, which can tell you whether a given website is a source of malware. Wedged between that and the omnibox is a button for quickly sharing the current page on one of a number of popular social networks (Facebook, Twitter, and LinkedIn).
Like Iron, Dragon has a bundle of under-the-hood changes that address privacy issues, many of them identical to the changes Iron implements, such as removing the Chrome client ID system, RLZ tracking, and error-reporting mechanisms. Another addition is an option to suppress the HTTP-REFERRER header, essentially an implementation of the Do Not Track policy. That said, regular Chrome users could use Google's own Keep My Opt-Outs add-on to achieve much the same effect.
Other new options include allowing incognito browsing by default and clearing history and cookies automatically at exit. Dragon also uses its own custom updater, not Google's, again as a privacy-protection measure.