I think the shake lights get a bad rap.
Yes, they're pathetically weak even as compared to even some premium coin-cell keychain lights, and we've all made and heard the jokes about the "solitary male entertainment activity" that charging one up resembles just a bit too accurately.
However, if you look past some of the hyperbole in their marketing, the AIT Nightstar has some impressive features. (Of course, some knock offs are a complete fraud, running directly from hidden coin-cell batteries.)
The magnet is buffered on both ends by opposing magnets, with rubber padding for backup should the light be dropped, keeping mechanical wear and tear to a minimum.
Unlike crank or squeeze lights, it is COMPLETELY SEALED. It never needs to be opened, and there are no open seams or pathways into the lights interior at all. The switch is really just an externally mounted rotating magnet that activates a magnetic reed switch inside the body, right through the plastic wall with no breaks.
In complete or near darkness with dark-adapted eyes, the newer models with a Nichia LED and a reflector provide a useable amount of light. Threads on this board are common where people complain that the "Low setting" on light XYZ isn't "Low enough".
In a long term disaster or collapse scenario, say decades long, even the best equipped flashaholic or survivalist equipped with solar cells and rechargables will run out. I agree, (and hope,) it's a long shot, but I can't rule such a situation out completely. Rechargables only last so long, and for so many charge/discharge cycles.
The idea of a completely self-sufficient piece of 21st century technology that has an indefinite lifespan that never needs further outside support from our technical/industrial base is appealing, however limited it's capablites are.
If all your other basic needs are met in your collection, squirreling one or two away couldn't hurt. Perhaps even as loaners to friends, neighbors, or family that you want to have lights, but don't want to be obligated to give them logistic support in the form of batteries forever.
$20-30 bucks is cheap insurance that you'll always have a flashlight, as long as you've got one working arm.