For the Modelfair Exhibition 2009 I made a cantilever bridge based on the Forth Rail Bridge and the Quebec Bridge. Not a copy of but in the spirit of.

Click the image above to see a pdf copy of the exhibition poster I made up for the bridge. I hope I haven't infringed too many copyright laws, but it was for personal, non commercial use.

For some reason I didn't take any photographs of the model, but you can see the bridge on the 2009 Modelfair page and the video.

I put some OO gauge track across it on a plywood base and had the Hornby Patriot class Duke of Sutherland with four coaches running across with a return loop at each end.

I do however use AutoCad in my work so  have started to make the Meccano parts in 3D and I built the model on the computer

I built each section separately and then put it together as an x referenced model. (if you don't use Autocad then you won't know what that means. I used to teach Autocad, and trying to get the concept across to the students was difficult at times so don't even try)