For the start of the ideas series, go here.
It's hard to overstate how much better TVs and TV shows look now than they did before the HD flatscreens. The first time I really noticed this was when I watched the 'Planet Earth' series from the BBC a few years back. The shots are gorgeous. You could turn off the audio and still enjoy what you're watching. As far as I can tell, no one has really taken advantage of this.
This idea is somewhat inspired by various music channels carried by cable companies. The channels are divided by genre and they largely serve as radio stations. You turn one on and go about the rest of your business. In other words, it uses the TV in a different way than the general intent. This idea would act in a similar way.
The idea is that you'd have a set of channels that would be nothing but nature scenery. One channel might be an endless series of beach shots. Another would be different views in a forest. Maybe an ocean reef or tours of the National Parks. The ideas are endless and with some testing, it wouldn't be hard to figure out the best views with some testing. I'd strongly suggest a channel that would be thunderstorms. Maybe a different one would have sunrises and sunsets in the mornings and evenings.
The music channels often take up a block of ten or twenty channels and this would work in the same way. Each channel could have a general theme and modify during the day for variation. The viewer could select what they want and simply enjoy it like they would a window view.
Maybe even a channel that would involve tours of various museums. It could be fascinating to have a new classic painting on your TV every few minutes. Maybe include some facts about the works and the artist.
I'm of two minds about the audio. Would it better to have natural sounds or perhaps thematically gentle music to accompany the video? I'm not sure. Maybe the preset would be one way and the alternate audio channel (SAP) would go the other.
I don't know how to make money with this. Advertising would be tricky. If it was involved, it would have to be very, very subtle. I do know that if this was available, I'd use it all the time. And I bet that I'm not alone on this.