My club has a couple of the K-Line camera cars and the kids love them when we run them at our show. Having said that, they are old tech, bulky, and with frequent dropouts.
There are wireless cameras that are slightly smaller then Gunrunnerjohn's. I have a couple of them and am installing one in a dummy GP-20 looking out over the short hood. When I tested one on another diesel it was a lot of fun running the train that way. I even went upstairs, hooked it to the living room TV and ran the train with my Cab-1. I found these at a R/C helicopter store online - on sale for $30 apiece including receivers. I also have some other cameras....a X-10 and a couple of wired surveillance cameras. I have those installed trackside and they give a nice standing-by-the-tracks sort of view.
