Chromium OS vs Archbang

Since you only have the browser, you cannot install applications (outside Chrome Apps which are decently protected by their limited API and the Chrome Web Store). This means no harmful virus, and also nearly no way you can screw your system. Everything will just work.

Chromium's system UI uses as little screen space as possible by combining apps and standard web pages into a minimal tab strip: While existing operating systems have web tabs and native applications in two separate strips, Chromium OS combines these, giving access to everything from one strip. The tab is the equivalent of a desktop application's title bar; the frame containing the tabs is a simple mechanism for managing sets of those applications and pages.

Because Chromium OS is designed for users who spend most of their computer time on the Web, it is intended for use in computers with little local storage and fast boot-up times.

ArchBang is minimal but completely functional out of the box. It's still up to you to set up to your liking. You still get Arch's unmatched documentation, insanely vast number of packages (in AUR) and extreme customizability. And a small but friendly and approachable community.

Being based on Arch, Archbang follows a rolling release schedule, ensuring that the software will always be on the bleeding edge.

Archbang is a pretty lightweight distro. It uses Openbox as a Window Manager by default, without having the need to use a desktop environment which would only bloat the OS further.