I'm not joking at all, the music is just so bad to me that it's seriously torture. I cringe when I walk by bars and clubs playing it. I leave bars the moment someone knocks a jukebox into it, it literally grates on my ears like someone scratching a chalkboard. I really really really dislike the genre nowadays.
The only problem with your question of what did I like is that I've never really been one to care who did a song, the only thing I typically know is I just liked a song. I never go out of my way to find out the artist or the name of the song, I'm just weird like that. With that being said I really can't name too many artists and I can never name any songs. This is even true today. I find myself listening to a lot more rock than anything as the lyrics just feel way more thought out and typically have much better messages than the majority of the current HipHop and rap genres. Do note I'm not comparing ENTIRE genres here, just majorities.
Now that that's out of the way I recently came across Eminem again and I feel like he's kind of an exception to my rule. He still raps like he used to and hasn't changed with the genre. It's kinda refreshing. Snoop dog has changed, his music sucks now. Black Eyed Peas have changed for the worse as well. I can't really think of any other names, but I know many music examples but again, I don't know song titles or artists so it's impossible for me to find them, nor will I subject myself to the torture of trudging through modern crap just to figure it out.
Edit: On a side note I have to agree Samurai Champloo and Afro Samurai are also exceptions to the rule. The music in them is very fitting and kinda just flows with the series, but by no means will I listen to the tracks without watching the anime.