Subscribers would be able to go to a web site and see thumbnail views of streaming video coming from the front of trains traveling down scenic routes in real time. You could pick the one you want and switch to full screen mode, maybe taking a short trip through some snowy mountains when it's a particularly humid day where you're living, or letting your mind wander as you travel down the tracks watching the fall leaves for awhile. If you're feeling miserable and it's a pleasant day outside you could zoom in on a train traveling through a dreary, rainy day. And vice versa. Done well, you wouldn't even see the train behind you as you floated down the tracks.

To make the business a success there would have to be a lot of cameras to choose from (increasing the scenery options) so railroads that allowed the cameras on the front of their engines would get a share of the subscription dollars. If more variety was needed, the service could be expanded to include cameras on subway trains and commercial planes. The view from a plane might be especially refreshing - it would look like you're floating through the clouds.

There are a lot of train ideas on this site so I might have missed this one. Just let me know if I have and I'll delete this.