I was on my way back from the Midlands last night approx 2:30am and happened to overtake a Peugeot 106 on empty motorway. We were the only ones on the road. It seemed he didn't like it and came tearing up behind me. I kind of went for a while and then slowed because he seemed to want to prove a point. Then at one point I slowed and stayed in slow lane but then he was neck and neck even going down to like 50 on empty motorway. I didn't want to undertake and so overtook and sped off somewhat, then once again up he came. So eventually I was in the slow lane again with him in front of me and he was on purpose going at like 40 to annoy me. The whole thing wound me up and I felt harrassed. Obviously in the ///M I could have left him for dust if I wanted but I was not prepared to break limits. What do you do about idiots like this?