- Hey, It's That Voice!:
- "Repentance", from Systematic Chaos, has Jon Anderson, Steven Wilson, Chris Jericho, Corey Taylor, Dave Ellefson, Steve Vai, Joe Satriani, and then some.
- Doug Pinnick sings a part in "Lines in the Sand", from Falling into Infinity.
- What Could Have Been: Falling into Infinity was supposed to be a double album, but the record label wanted it to be less proggy and more radio-friendly. Also, a shorter version of the song "Metropolis Part 2", before it was turned on an album, was going to appear in the second disc.