A roster of the sagging shelf of books with "agile" somewhere above their folds. Or books that would have if they'd been printed after the infamous AgileAlliance meeting.
Add'em here as fast as you write'm, folks!
eXtreme .NET: Introducing eXtreme Programming Techniques to .NET Developers
ExtremeProgrammingApplied: Playing to Win Ken Auer, Roy Miller (because although XP Explained taught me what to do, XP Applied taught me how to do it, practically and without ruffling too many feathers.)