Chromium 58.0.3018.0 + Portable
The interface is identical to Chrome's and in addition, it has the exact options as its more popular sibling, as well as extension and theme support. While the asymmetries between the two browsers are not that many, the ones that do apply make quite a difference.
Unlike Chromium, Chrome also comes with an integrated flash player, the company's autoupdate function that's being used in many downloadable tools plus some other improvements to help the software rise up to the expectations.
Despite the contrasts between the two, Chromium is actually a pretty fast browsing solution. It's true that its simplicity may not captivate the whole crowd and some users might feel the need for some features that are only available in Google's very own tool.
In case you're looking for a simple web browser that helps you do just that, browse the Internet, then this might be a great tool for you.