A hydrogen powered plane was tested in England. It took place in Kemble which is in the Cotswolds. The article is fairly advertising the idea, but it's still cool that it could work. They had a regular engine in case the hydrogen powered one didn't work or failed midflight.
There is a language to command cells to attack cancer. It is being learned.
I find one of the great joys with seeing technology improve is figuring out how to synthesize the best aspects of older tech (elegance, simplicity, and to an extent reliability) with the best aspects of newer tech (mostly orders of magnitude more raw performance or lower cost, but also technological improvements like improved encryption algorithms or more efficient digital audio/video standards).
Eg. setting up one of those old text-based BBS servers you dialed into with a 56k modem, except it's all encrypted and has high-quality voice chat. Would be way more reliable than something like a discord server.