Here's my list of test tracks for bringing up new players etc.:

Orbital, The Naked And The Dead from Halcyon (stereo soundstage)
Art of Noise, Close (To The Edit) from The Best Of (stereo soundstage)
Crystal Method, Busy Child (Uberzone Mix) from the import of Tweekend (bass)
Susan Cadogan, Fever from Cosmosonica (bass, vocals)
Kirsty McGee, Safe Harbour Song from Frost (vocals, shiver-down-spine)
Stone Roses, Made Of Stone from Stone Roses (shiver-down-spine)
Placebo, Pure Morning from Once More With Feeling (rawk)

Peter