Some good shouts in this thread
NMH - In An Aeroplane Over The Sea
Modest Mouse - Good News For People Who Love Bad News
Titus Andronicus - Airing of Grievances
Wilco - Yankee Hotel Foxtrot
Flaming Lips - Yoshimi Battles Pink Robots (If TFL can be counted as Indie.. I think they can.)
Off the top of my head, to give these albums to someone who doesn't really know what Indie is about would work wonders.