There was an interesting take on this mentioned on the Daily Politics Show today. In essence when we finally hammer out a deal with the EU on what Brexit will actually mean for Britain, there could be another referendum put to the electorate to decide if we want to go ahead with the negotiated terms or might we want to think again.
Careful now - in my experience Leave voters generally wail and gnash their teeth when something like this is suggested as they want Article 50 enacted now regardless. However, try asking them why they voted Leave and what they will accept as the terms of Brexit? I've yet to meet one that seems to have thought this through to a logical conclusion. Unless of course our hatred of the EU is so great that we don't care what deal we get.