This celebrity feud is ending just when it was possibly about to get really good. After former American Idol judge and Aerosmith star Steven Tyler criticized the current panel of judges, Nicki Minaj (one of the aforementioned show's present-day judges) took it personally, calling him a racist and telling him, "go f--k yourself." Tyler later apologized. Tyler may have helped pioneer rap-rock mash-ups with Run DMC's "Walk This Way," but he isn't the first rock star to lash out at their rap peers. Click on for other examples of cross-genre beef between rappers and rockers.
(Photos from left: Larry Busacca/Getty Images for Pepsi, Christopher Polk/Getty Images for Clear Channel)