When I moved to Germany in 2001, I managed to drive for about 20 miles on the wrong side of the road, only realising when I woke my wife to point out the maniac driving at me on my side of the road by screaming like a little girl
On my first Autobahn trip, I was in 1.6l Vauxhall Astra, thinking I was a proper rude-boy because I was legally driving at 100mph, loving life. I then saw a lunatic flashing his lights behind me and I remember thinking 'What's his problem?'.
Turns out his 'problem' was that when you're doing about 160mph in a Porsche and some knob from the UK is in your lane at 100mph, you catch up quite quickly
After being flashed out of the way a couple more times, my lane discipline was sorted right out and remains good to this day
Returning to the UK after 4 years of living in Germany made me hate both the UK roads and the standard of driving we see regularly (by the minority of drivers it must be said).