The twelve greatest fictional detectives (who aren't Sherlock Holmes)

At io9 Esther Inglis-Arkell tagged the twelve greatest fictional detectives (who aren't Sherlock Holmes), including:Alex Cross

Alex Cross, the protagonist of a series of novels that begin with Along Came A Spider, is the most soft-spoken member of a list that includes several little old ladies. His habits include playing the piano, owning a contented cat, and quietly observing social injustice.