One very nice train ride has been VIA Rail's Ocean from Montreal to Halifax. The train leaves Montreal at 6:00PM and arrives at Halifax at 5:00 PM the next day. Departure from Halifax is around Noon and arrival in Montreal at 9:00 AM the next day. When we rode it two summers ago the schedule allowed us to take the train all the way from our local VIA station in Kitchener, ON, changing in Toronto and Montreal (either worth a trip all on their own). Sleeping cars are new, but if you are in sleeper+meals class you can access the vintage Park car observation-dome-lounge (called "Park" because the cars were all named after Canadian parks by the Canadian Pacific when originally built in the 50s). Anyway, the Canadian government in its infinite wisdom has already cut the train to 3 days per week and now it may be eliminated completely. It is not as spectacular as the Canadian between Toronto and Vancouver, but also not nearly as expensive. You travel through Quebec, New Brunswick and Nova Scotia. If you have the time in the next couple of months, this may be it.