A long time ago at work, I was given a Logitech K750. It is powered by solar cells which charge an internal battery. It works so well, I don't understand why there aren't more solar powered keyboards.

I ended up buying the same keyboard for home and I really enjoy typing on it. My only complaint is that it's difficult to remove the keycaps for cleaning and some dust somehow got inside and I can see it on the little solar panels.

Typing preferences are very subjective, but I've grown to really enjoy working on this keyboard. I've used it so much that the texture has pretty much worn off of most of the keys and I'm starting to lose the printed letters on the key caps. I've thought about buying a few replacements and storing them because no product is sold forever...