Naah, you guys are all out of touch with what the average non-audiophile is impressed by. Here's how you do it.
1. Get something that produces a lot of bumpin' bass, like a Beyer 770.
2. Get an amp with plenty of power to drive your chosen headphones. Doesn't matter which one, really.
3. Get a copy of "Cheap Subwoofer One-Note Booty Bass Classics, Vol. 1".
4. Crank up the volume to ear-damaging levels, sit back, and smile proudly while the non-audiophile yells, "WOW THESE HEADPHONES REALLY GO LOUD!"
5. Go home and listen to some real music while you apply bandages to the part of your soul that you injured when you pretended that going loud was indeed a good headphone system's primary virtue.
Speaking slightly less facetiously, a Sony V6 usually impresses non-audiophiles. The smiley frequency response matches what they're probably used to, the bass has pretty good impact, and the grainy highs convey the impression of lots and lots of detail.. and despite the fact that they are often maligned, they really do have enough fidelity for the "I've never heard these things in my music before" effect. Plus, they're so easily driven that you don't need to worry about inadequate equipment.
I often recommend them to people getting good headphones for the first time, actually.