When I have nothing else to do, I like reading random articles on Wikipedia. You can press Ctrl-X there to get a new random article. This doesn't work, though, until you have clicked somewhere within the shown page, regardless of whether you have scrolled by PgDown before or not. It seems the focus isn't on the page itself after loading. That worked in OW 5.1.3 (not in SP15, though, probably has sth to do with WebKit integration). Please fix that, it can be rather annoying. X-)