Predicting places from names in the UK

You've probably looked at distribution maps for surnames in your family tree. http://worldnames.publicprofiler.org/ is freely available and for the UK there's http://gbnames.publicprofiler.org/
There's an interesting new site, part of a University College London research project, which looks at the distribution of two names together showing where a couple or friends with those two surnames might have met. It's an alpha quality product and they're asking for feedback.
I tried with two names, one strong in parts of Scotland, one mainly from the London area. The resulting map highlighted both areas -- hardly surprising. London happened to be where they met.
You can also look at the distribution of single surnames on a database which may be more current than available elsewhere.