If you have a recent Mac with a UK English keyboard, you might have noticed that nowhere on the keyboard is there a key with the # symbol (aka hash in the UK, aka pound in the US). I have lost hair trying to find out how to print one without resorting to the character palette. I just found the answer to the problem on HTML Dog: press left alt + 3. Similarly, to obtain the € symbol, press left alt + 2. However, the € is marked on the keyboard, the # symbol isn't. Surely Apple could have gone the extra mile (or rather the extra nanometre in this case) and marked the # symbol on the keyboard? Or maybe they could have used the same UK English layout that is used with PCs? Anyway, that's one mystery solved.