Yes, yes, as usual I'm a week late on this one. A Royal guardsman has clipped a tourist round the back of the head who was imitating and irritating him. To be honest, I think the tourist deserved it.
As an interesting aside, I was watching QI the other day and discovered that the you can tell the members of the Guards apart by the buttons: "Evenly spaced buttons mean that they are in the Grenadier Guards. When the buttons are in pairs, they are in the Coldstream Guards. Threes represent the Scots Guards, fours the Irish Guards and fives the Welsh Guards." That means our man is in the Scots guards, but I'm not sure- it's hard to count buttons from a low quality still!