I love Third Day - you should get "Offerings II," it's a good CD - some live songs mixed with some studio songs.
There are alot of Christian metal bands making a big impact on the mainstream metal scene. The Agony Scene, As I Lay Dying, Norma Jean, Demon Hunter, etc. The cool thing is these bands get heavy rotation on metal stations like Sirius Hard Attack and the DJs will mention the fact that they are Christian frequently.