Ok, thanks guys!
tsutton didn't even know about that site! Thanks - just seen they've got an iPhone app for it aswel! Touch!
Ok so next q' : which route? Google suggests either M11 > A1, or M25 > M1, with the latter being 30miles longer.
Since I don't go up that way often (well, never

) would I be best going A1 or M1?