Here are a few of my favourites. First, disused VIA Rail RDCs sitting at the Halifax station. This photo is great not only for the RDCs but also for the view of the old train shed.
Here's a rail removal train in Newfoundland, parked for the weekend. Jon caught the very end of the Newfoundland Railway.
Here's CN train #6 ready to leave Sydney, Nova Scotia, in 1958, a slide by John McIntosh.
Finally, here's a 1953 shot of a Newfoundland Railway steam engine. There are a lot of Newfoundland Railway photos and slides in this stream.
Please go look at all of Jon's Flickr stream.