Nirvana in no way cntributed to the rock-rap of the likes of Limp Bizkit or Kid Rock, neither of which I can stand.
Rather, they and the rest of the grunge movement influenced outstanding musicians such as Chris Cornell of Soundgarden, and now Audioslave.
Or the heart-stopping vocals of Amy Lee of Evanescence.
What about Scott Stapp of Creed, whose awesome lyrics have helped me return to my faith?
And POD, another great Rock band with a great message?
If you want to compare apples to apples, try the annoying Beastie Boys. They helped "white boys" become rappers.