My Top 25 of the '00s includes one of the best Christian rock songs which I'd label somewhere between "metal" and hard-rock. I haven't heard the song on mainstream radio stations, but it sure should get a lot of airplay on all rock stations.
The song is "Fire On the Inside" by Pillar. It's a great song! Check out their website by clicking on Pillar. You can listen to the song on their website.