Actually, Kevin, that's a really good thought: providing a list of different minimalist works that are all about an hour long, in case people get sick of one or the other. As long as Mr. Glass figures prominently among them (which he would anyway), that should be enough for the requirement. Reich's Music for 18 Musicians would be terrific, as would Glass' Music in 12 Parts, and some of John Adam's dances. Since most CDs tend to be about an hour long, that should work nicely.
Eric, I'm not familiar with Kim Stanley Robinson, but it seems like most of the Amazon reviewers loved that book except for the final two chapters. I'll see if I can track it down. Also, on a similar theme you should check out David Mitchell's Cloud Atlas, which blew my mind a few months back.
Now I just have to figure out what to DO with the mandala... :)