I'm a simple guy. How about a 12" PowerBook simply sporting the specs and options of the 17" PowerBook: 1.5GHz G4, 5400rpm, 128MB graphics, two available RAM slots, light-up keyboard, etc. In fact, I'll even do without the PC slot and FireWire 800, since I don't see either one making an impact on my Mac using life.
But maybe a few upgrades like 8x SuperDrive and the latest, greatest honkin' graphics card?
That's it, really. If we get slightly outrageous, how about the specs of the new 20" iMac G5 crammed into a 12" iBook?