I've just been reading an article in the Sunday Times 'Driving' supplement about a version of the new VW Passat (from October 2014) that has a 'Trailer Assist' option that allows drivers to back their caravan, horsebox or trailer into place completely 'hands off'.
Apparently, the driver uses the rear view mirror directional adjustment buttons to place an image of the trailer where s/he wants it to be on a dashboard screen and then all s/he has to do is engage reverse and then accelerate and brake as instructed for a perfect result.