Clare has managed to push my family tree of male ancestors back to a John Seel, born in Oldham, Lancashire, in 1847. We have no idea what he looked like.
A while ago there passed away the last generation of which this could be true. Consider the .wmv movie of Adrian Seel, here. As I was taking it, I was conscious that despite the poor resolution and 2D technology, it is easy to anticipate a future technology - based on 3D modelling - which could transform this video into a high-resolution 3D object: all the information required is either there, or can be extrapolated.
Technology forecasting: take something which would be good to do, and where in principle we know it can be done. It will happen - 10-20 years max.