Mixing rap/hip-hop and metal/rock what do you think?

I want to ask what do you think of hip-hop/rap and rock/metal being mixed?

I think there some attempts or bands doing and its really works. Some are doing it and I think maybe one genre covers the other up too much..?

I got to thinking about this after there was question on—-> hip hop/rap http://www.fluther.com/disc/70763/did-you-know-there-was-a-diffrence-between-rap-music-and/

Also if you are one those I only listen rap, cause I am freak’in G or I only listen to real music “rock” then seriously don’t answer with BS.

Only please do turn me onto bands/artist that you know of. I also tend to lean on older music I mean like 90’s 80’s etc….The newer music from 2000 and now is eh okay compared to older music but thats just me.