Ratscalibur (A Chronicle of the Low Realm), by Josh Lieb
An uncle gives the kid a rat for a pet, and it talks. How cool a relative is that?
I'd read more and was sorry the sample was so short.
I really like to read a sample of the author's other book: I Am a Genius of Unspeakable Evil and I Want to Be Your Class President. How cool is that title?