right i want proof im not mad, about 20 years ago or so i had these little bean shaped things that moved and jumped when you held them in the palm of your hand, does anyone remember them and if so what made them move? (Hurry i hear a canvas jacket)
I remember having some years ago and they turned out to be capsules (like you get some drugs in) with a small steel ball-bearing indide which rolled from end to end. You can still get them - saw them for sale in Asda only today and nearly bought some in a fit of nostalgia.
They could be something to do with a fly of sum sort, but I can remember reading something about they where an insect case and ofcourse when the insect moves so does that case thing :) happy hunting for a good answer !
I saw a great TV program on this once. They are the seed of certain Mexican shrubs, especially those of the genus Sebastiania, of the spurge family (Euphorbiaceae), that contain larvae of a small olethreutid moth (Laspeyresia salitans). The movements of the larvae feeding on the pulp within the seed, which are intensified by warmth, give the seed the familiar jumping movement.