At 8pm on sunday night (20 dec 08) i was driving into oxford. While sat at the traffic light controlled roundabout where the ring road dual carriage way exits to go into oxford 3 royal mail trucks (small lorry types) approach from behind at speed. The where waitin in the que but edging closer and closer until inces from my rear bumper. As the lights changed all 3 tried to get in fron of each other, cutting across lanes and nearly hitting 3 cars in the process. Clearly racing each other to the nearby depo they showed no respect for other road users or the law. Just off the roundabout i found myself being over taken in a 30 mph zone by one of the trucks, now travelling at least 45 mph. As the road came to an end he pulled across (all while the second 2 are within a few metres of my bumper) forcing me off the road and taking my mirror off in the process. They then proceeded to give me the (w*nker) symbol from there now open window. I got out of the car to inspect the damahe at which point the first van proceeded to come right round the roundabout and start shouting abuse (along the lines of f*ing idiot, waiti there your f*ing dead). As he attempted to 3 point turn in the road i got back in my car and drove away as fast as i could. I have no witnesses other than those at the earlier junxction (who did not stop) and the drivers of the royal mail vans, andid not get the registration otherwise iw ould go to the police.