Here's a really interesting one.
The Leek and Manifold Valley Light Railway was a genuine 30" gauge railway (just for you "n30" fans out there) in Staffordshire in the UK. Pretty little line with beautiful engines. It would make a great model, actually.
What's unique about it is they used tranporter wagons European Style to move small standard gauge freight cars to customers along the 8 mile route. (Not practiced anywhere else in Great Britain). As a result there were isolated standard gauge sidings scattered along way.
What's even better to me, as a fan of old films of narrow gauge trains is there's a YouTube video of them doing it!
http://www.youtube.com/watch?gl=GB&hl=en-GB&v=dWZbZGGnE6E