I heard about this whilst watching the BBC Top Gear motoring programme last night and had to give it a go… The RAC‘s route planner on their website is a great tool, but try entering a route from Nottingham to Bideford, avoiding motorways, and the system will return a 1070.9 mile (1723.4km), 42 hour and 24 minute route via Ireland and France (at least until Map24 patch their software)!
Strangely enough, if you enter the same route using the Map24 site it doesn’t seem to get lost in this way.