To dave-in-nj: I don't think there should be any logic in something that could be possible in the future, unless you have been there before. You can only assume it could or couldn't be possible.
To all your questions maybe, you are already trying to fly now. I'm still trying to crawl. By proving I can light up a LED by a reading off a temperature, would be the first step. To lighten/ darken the LED would be another huge thing for me. I'm now not trying to create a billion dollar/pound/euro idea, maybe it is or isn't, who knows. Right now I don't really care about that, I want to prove my concept works a.k.a. proof of concept.
To TomGeorge: Yeah I'm aware of the Peltier but is it innovative? It already exists. Again I'm not really trying to heat or cool actual stuff but to simulate it can work.