Ensable readings of audiobooks are great when done well. My favorite is a recording of the His Dark Materials series narrated by the author and with different voice actors for all characters.

For something a bit more classic (and free), I also really enjoyed the Librivox Dramatic reading of Dracula, though some readers come off better than others.

In both cases, the books really lend themselves to the format: in His Dark Materials, there's near constant dialogue since every character has a companion spirit to chat with, and Dracula is written as a series of letters and journals so each chapter follows a different character's perspective and style.