I have several wind-up flashlights, the Chinese versions, bought on a sale 1-1/2 years ago. I see the same models all over the place now, including Costco.

My experience with these has been mixed. The LEDs are bright (for close-up flood use), the winding mechanism is noisy yet functional, ... but the batteries are junk. A few months after purchase, one of them stopped holding a charge for more than a half hour or so. I opened one and discovered there is a tiny lithium-ion button battery inside. I guess I could replace it, but it seems like throwing good money after bad. That light became the "kid flashlight." The others are working, but I wouldn't trust them without a good backup. (One day I may convert it into a cell phone charger -- not hard to do.)

However: the Freeplay-powered crank lights are another thing entirely. They are heavy and very well made, with good NiMH sub-AA cells inside. I would trust one, though I'd need a Sherpa to carry it for me :-).

As to the shake lights: every one I've seen is garbage. Unless there are shakers that are much, much better, I would say "forget it."