In reply to satori:
Yes, I found out! I was about 12 and I'd wandered through the kitchen and randomly taken a handful of beans that were soaking, as you do; the effect, several hours later, in the middle of the night was severe - was on the floor unable to call out for help for some time - very poisonous! It was very frightening.
(Prefer tinned kidney beans now! I don't like tinned baked beans though, except when there's no alternative, extremely hungry, or outdoors -with Worcerstershire sauce).