Since the strength of a black hole technically hinges on its size (deciding the boundary of its event horizon, or the so-called point of no return), could we possibly put one of them in our pocket without consequence (or at all)?
WATCH: "Could You Put A Black Hole In Your Pocket?"
As a side note, physicists have suggested that the Large Hadron Collider could theoretically create micro back holes. In the case that it did, a baby black hole still wouldn't do any damage, as it would take well over the universe's current age for one to consume a milligram of matter. By that time, it would have evaporated into nothingness anyway.