When I was first introduced to TTD a few years back, I trained and developed my skills on the great map The West Country. It was a simple map of the West of England and Wales, but with lots of roads connecting the towns, unlike other maps. It was the best map by far on TTD.
Then earlier this year I found Open TTD. I soon realized I needed to transport The West Country onto it. So I did. But in the original version were some annoying deviations from reality. I started correcting these. With the release of OpenTTD 0.6.0 I am releasing my first version with motorways properly implemented. Next stage will be to put proper motorway junctions on, but for now be happy with the first version of [pauses for the non-existent drum roll] the revamped The West Country.
Update, 8th March 2008. Scenarios now separate. V1.0 included for those more train minded.
Update, 18th October 2013. Original West Country now has single bridge for Second Severn Crossing.