That was very interesting. Kind of reminds me of Cypherpunks Semi-Arch-Nemesis David Brin's "Earth", where people messing around with small black hole creation cause the risk of Bad Things happening. In practice, we're less likely to see black hole computers developed than Nanotech Grey Goo computers, At 01:41 PM 03/31/2001 -0600, Jim Choate wrote:

PROGRAMMABLE BLACK HOLE COMPUTERS. One usually thinks of a black hole as an omnivorous object swallowing energy and spitting some of it back in the form of Hawking evaporation radiation, consisting of particles created in pairs out of the vacuum near the edge of the black hole. In principle, a tiny black hole can be formed in a way that encodes instructions for performing calculations. Correspondingly, the answers could be read out from the escaping Hawking radiation. Why use a black hole at all? .... of detecting gravity waves with LIGO and other interferometric

Does "LIGO" stand for "Light In, Garbage Out"? :-)