I'm trying to use a UK keymap on a physical US keyboard on my notebook (Asus Zenbook UX31E). My keyboard has vertical bar and backslash (| and \) above the Enter key, but I get hash and tilde instead. On UK keyboards, pipe and backslash seem to be just to the left of the Z key. Unfortunately, I don't have that physical key at all; instead, I just have a fat left Shift key. They needed an extra key to make room for £ and €, so things have moved around a bit, I guess.