Do these gadgets really work?

Has anyone ever bought or tried out those items to jump start a car that plug into your cigarette lighter? There's one that goes from car to car (in the lighter). There's another that you charge it up and carry around with you and plug it into your lighter for about ten minutes to get you started.

Does anyone have any experience with these things? Do they really work?

I don't see how something like that would work to get your car started since the lighter draws its power from the battery too. If your battery is dead the lighter wouldn't work.

you plug it into another car.
dur.

i dont think it would work.
your cigarette lighter socket can only handle so many amps before it will blow a fuse.
it would either blow a fuse instantly, or take half an hour to charge it enough for one small crank.

best bet:
go get a set of jumper cables

Its fine if you just need a tiny trickle of juice for a battery that is almost capable of cranking the engine without help... but as far as an actual jump start? Nope. Sometimes a dead battery won't even succeed being jumpstarted by a dedicated set of 4-gauge jumper cables, so some 16-gauge wire won't really do much good.

i have a little battery pack that has cables that you hook up directally to the battery and it worls great if your car turns over even a little but if the batterys dead it wont do much.