Making a thread for this one…
How about an Anker Power Jacket
Comes with speakers and headphones built into it the jacket, you can switch if the music comes out of one or the other.
Jacket has a build in powercore for charging your devices.
Jacket has some solar panels built in somewhere so you can lay the jacket out or wear it and charge your powercore.
Also jacket has small LED flashlight built into the sleeve so you can point your arm and use the light.
The components are given the waterproof treatment.