Many years ago, at some Expo or other, I acquired a flashing plastic ball that seems rather different from the usual ones I've seen. (Apparently a promo from RapidMind, which was bought by Intel long ago, so there's no use going to the source!)
For a start, it's translucent (uncoloured) plastic but perforated, with the outer holes going all the way through.
I always assumed that like all the others it just had a battery and a motion sensor plus a chip to control the flashing. After being tucked away for those many years, though, it no longer flashed when bounced. I just thought the battery had given out.
However, I was idly bouncing it more extensively a couple of weeks back, and was astonished to see it flashing again, and getting brighter the more I bounced it! I deliberately left it alone for a few days and tried again. Once more the initial flash was dim or absent and got quite brilliant again after more shocks.
This behaviour is entirely consistent over several repeats, so I'm wondering if it could possibly be an ultracapacitor and some kind of piezo charging circuit. The relevant voltages and currents seem all wrong for this though.
I also have a couple of examples of the more common "Magic Ball"
-- similarly acquired, and also apparently now dead. I cut one of them apart and found the expected couple of watch batteries and a spring tremblor. I also found that removing and reinserting the batteries brought it back to life! (Yes, the contact was thoroughly corroded.)
The behaviour is different, though. The revitalized ball is always at full brilliance (though I can't actually bounce it, as it's in two halves!). I suppose it's conceivable that the mystery ball just has a corroded battery contact, that somehow becomes more conductive each bounce, but it's remarkably consistent for that. I do *not* propose to cut it apart! Too intriguing.
Has anyone else got experience or knowledge of such a beast?
Ta,
-- Pete --
[I somehow get reminded of the "Interocitor" of ancient days... (:-))]