A long-term project of mine, started way back in 2010. This scenario is set in a fictitious group of islands in the Outer Hebrides during the North Sea oil boom. There's a well-developed existing road network which links all the starting industries as well as the towns (the lack of this has always vaguely bugged me) and about four raw materials producers for every processed products supplier; some of the latter are use it or lose it, so act fast!
AIs tend not to cope very well with this map, so I recommend playing it solo except for TownCars or StreetTraffic, or hosting it in multiplayer.
More detailed screenshots to follow, but here's a whole-map shot that was too big to attach: hosted on Box.com
Edit: Since planetmaker asked over IRC, the map size is 256x256 and the NewGRFs are... Well, just take a look:
screenshot#5.png [32.81 KiB]
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All of them are available on bananas, and up to date at time of posting.