Singularity by Bill DeSmedt is a a science fiction story that has been made into a free audiobook. He also offers Doctor Jack's Soapbox Seminars, a nonfiction audiobook that discusses science behind the events in Singularity.

What if the cataclysmic Tunguska explosion of 1908 was caused, not by a meteor or a comet, but by a microscopic black hole?

What if that fantastic object - smaller than an atom, older than the stars, heavier than a mountain - is still down there, orbiting deep inside the earth, slowly consuming the planet?

What if only a rookie government agent and an uncannily-insightful consultant stand between a renegade Russian billionaire and his plans to use the black hole to change history - or end it?

What if it's all true?