To the person on Reddit who, just five months ago, pleaded with Logitech to "please start making solar keyboards again!," your wish has been granted. Following up on the launch of its solar powered K750 plank released way back in 2010, Logitech today introduced the Signature Slim Solar+ K980, a wireless keyboard that sips on light from any light source to stay charged.
That 
plea on Reddit hits a personal note with me, as I happen to own and use the K750 with my laptop whenever I travel. I can't recall exactly when I bought it, only that I've owned it for over a decade and it still works just fine. The only maintenance involved is to occasionally wipe down the solar cells, and that's mostly because it spends a lot of time collecting dust in a closet in between trips.
 
I love that keyboard, and if it gives up the ghost, I'll have to strongly consider the K980 as a replacement.
"Wireless devices free us of cables and hassle, but remembering to charge them can create unnecessary friction. Today’s users expect simplicity, reliability, and an intuitive, hassle-free experience that just works. Signature Slim Solar+ delivers just that. It stays charged without interruptions and is built to run for up to four months in complete darkness, so people can stay focused on what truly matters to them," 
Logitech explains.
 
Despite having "Solar" in the name, you don't actually need to plop the K980 in sunlight. It features a light-absorbing strip and, combined with Logitech's LightCharge technology, can generate battery life from ambient lighting, such as a lamp.
According to Logitech, users can expect up to 4 months of use in total darkness when the keyboard is fully charged. If it works as well as the K750, however, charging is not something you'll ever need to think about. Well, unless you do actually sit for months in total darkness.
One thing to note is that like the K750, the K980 is a low profile keyboard that's more akin to typing on a laptop keyboard than a standard deck. That said, it's a full-size deck with a dedicated number pad, a customizable action key, and the ability to connect to up to three multi-OS devices (depending on the model).
Note to Logitech, if you're still taking requests to bring back products, can you start making universal remotes again? Pretty please? I'm going to be devastated when the day comes that my 
Harmony Elite stops working.