They still open with As I Am occasionally. I think In The Presence Of Enemies Pt 1 is their best, most recent opener.
Ah hell, why not. In order of my liking the song as an opener:
The Glass Prison
Lines In The Sand
Metropolis, Pt. 1
About To Crash
Overture 1928 / Strange Deja Vu
In The Presence Of Enemies Pt 1
New Millennium
Home
A Nightmare To Remember
Pull Me Under
The Root Of All Evil
As I Am
I think The Great Debate and Honor Thy Father would both be pretty sweet opening songs, though I don't think they've ever done that. Hell's Kitchen as an intro to Lines In The Sand too. Also, I'm fairly certain they've never opened a show with 6:00.