I'm only half kidding. I'm a bit of a prepper and I have lots of powerbanks and devices that charge from USB but besides idling my truck I really had no other way to charge any of them in case of a long-term power outage which seemed a bit of an oversight on my part.
Not like this solves the issue. 30 watts (under ideal conditions) isn't much but it's a start.
Electric fire starter. Mesh nodes. Walkie talkies. Small computer with offline Wikipedia and Google maps. GPS may still be working for a while, so that would be useful to charge and use. Portable fans. MP3 player or other entertainment device. Camera. Small power tool batteries....
Yeah, in an apocalypse, a small about of electricity would be a luxury.