My first example is rather unconventional given that I am not really into rap music. However, Outkast does the trick for me. I don't know whether it is the cat across the street that sits in the windowsill all day long that made me think of 'Ms. Jackson' from 2001. But besides the groovy animals in the awesome video, it is also one of the most sincere and melodic rap songs I know. Perhaps my all-time favorite of the genre.
Bonus info: the song is actually an apology from André (the well-trimmed half of Outkast) to Erykah Badu's mother following Erykah and André's divorce.