some of the car carrier freight trains in North America has an articulated joint (2 cars max) with a plastic looking accordian like the ones you see on the articulated buses. It is not very popular as I rarely see them.
My Trackmaster/Tomy/Plarail Photo Gallery Page (over 600+ photos and still under construction)
https://www.flickr.com/photos/183311600@N03/
https://www.flickr.com/photos/183311600@N03/