Dr. Alex Filippenko (Astronomer at University of California, Berkeley) explains in May 2010, why we should not be scared of black holes, and what they can do.
Most adults are aware that black holes have an event horizon, beyond which nothing, not even light can escape, regardless of the energy of the photon. What other, less well known properties, might be interesting?
Why a black hole emits energy @47:57
At least 10x higher efficiency at producing energy than nuclear reactions. Can give rise to relativistic jets, possibly through action of magnetic fields.
Time slows when close to a black hole @59:02
Therefore 'time travel', at least into the relative future, possible.
Black holes evaporate @1:01:37
Small black holes evaporate quickly due to 'negative energy' capture. They produce gamma rays upon evaporation and when they 'eat' a lump of matter.
I hope I've convinced you that black holes form in nature only under very special circumstances. You need something to compress material into a very small volume, usually that something is gravity. We don't know of any other vices that will do this, so don't worry, be happy, a black hole isn't about to devour your house.
- Dr. Alex Filippenko, May 2010