The article briefly mentions the large amount of energy stored in the collider beams. In the LHC, "each unimpeded beam is capable of melting a 500-kilogram block of copper." This energy has to be dissipated in a few microseconds if something goes wrong in the collider. For the LHC, the solution is to heat a huge graphite cylinder to over 700 C.
Not as cool as a black hole, but a pretty neat engineering challenge.
Graphite stays solid at standard pressure up to 3900K (source: wikipedia https://en.wikipedia.org/wiki/Carbon) so you get ~3600K of ΔT from standard temperature of ~300K before you have to deal with a liquid or gas. Coupled with being denser than water (but having lower specific heat than liquid or solid water), my napkin is telling me you get about 10x the heat capacity in J/m³ with graphite instead of water.
Not as cool as a black hole, but a pretty neat engineering challenge.
http://spectrum.ieee.org/aerospace/astrophysics/cern-to-star...