[theendisney2]

There is or was a British inventor who build an odd contraption with 2 vibrating plates with grinded garbage flowing between them suspended in ferrofluid. Along the track the paeticles sort themselves by density. Innitially a silly idea as ferrofluid is expensive but he wanted to see how well it worked and possibly try better fluids. It turned out to produce much more ferrofluid than was consumed. The story ends with: no one was interested enough to spend money on it.