Firefox OS is a fully open source mobile platform, but it lacks many full-featured apps. Starting from today, RollApp provides full desktop apps for Firefox OS, including LibreOffice, OpenOffice.org, Tomboy, KeePassX and File Roller. The apps are loaded on RollApp cloud servers and are streamed using WebSockets, which make them run smoothly.
Web browser, powered by WebKit, which you can start by typing any URL in Tomboy and clicking on it.
UPDATE: Now you can run Chromium web browser in Firefox OS! It scores 9677 points in the Octane benchmark.
All RollApp apps can be found in the Firefox Marketplace.